diff --git a/queries/admin.sql b/queries/admin.sql
index 5b2f2ce..9bdfbcf 100644
--- a/queries/admin.sql
+++ b/queries/admin.sql
@@ -20,8 +20,8 @@ SELECT phone_number FROM users WHERE blockchain_address = $1;
 -- name: account-latest-transactions
 -- Returns the first page of a users latest transactions
 SELECT transactions.id, transactions.date_block, transactions.tx_hash, tokens.token_symbol, transactions.sender_address, transactions.recipient_address, transactions.tx_value, transactions.success,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.sender_address) as sender_identifier,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address) as recipient_identifier
+COALESCE((SELECT phone_number  FROM users WHERE blockchain_address = transactions.sender_address), 'SYSTEM') as sender_identifier,
+COALESCE((SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address), 'SYSTEM') as recipient_identifier
 FROM transactions
 INNER JOIN users ON ((transactions.sender_address = users.blockchain_address) OR (transactions.recipient_address = users.blockchain_address))
 INNER JOIN tokens ON transactions.token_address = tokens.token_address
@@ -30,8 +30,8 @@ WHERE users.phone_number = $1 ORDER BY transactions.id DESC LIMIT $2;
 -- name: account-latest-transactions-next
 -- Returns the next page based on a cursor
 SELECT transactions.id, transactions.date_block, transactions.tx_hash, tokens.token_symbol, transactions.sender_address, transactions.recipient_address, transactions.tx_value, transactions.success,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.sender_address) as sender_identifier,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address) as recipient_identifier
+COALESCE((SELECT phone_number  FROM users WHERE blockchain_address = transactions.sender_address), 'SYSTEM') as sender_identifier,
+COALESCE((SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address), 'SYSTEM') as recipient_identifier
 FROM transactions
 INNER JOIN users ON ((transactions.sender_address = users.blockchain_address) OR (transactions.recipient_address = users.blockchain_address))
 INNER JOIN tokens ON transactions.token_address = tokens.token_address
@@ -41,8 +41,8 @@ WHERE users.phone_number = $1 AND transactions.id < $2 ORDER BY transactions.id
 -- Returns the previous page based on cursor
 SELECT * FROM (
     SELECT transactions.id, transactions.date_block, transactions.tx_hash, tokens.token_symbol, transactions.sender_address, transactions.recipient_address, transactions.tx_value, transactions.success,
-    (SELECT phone_number FROM users WHERE blockchain_address = transactions.sender_address) as sender_identifier,
-    (SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address) as recipient_identifier
+    COALESCE((SELECT phone_number  FROM users WHERE blockchain_address = transactions.sender_address), 'SYSTEM') as sender_identifier,
+    COALESCE((SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address), 'SYSTEM') as recipient_identifier
     FROM transactions
     INNER JOIN users ON ((transactions.sender_address = users.blockchain_address) OR (transactions.recipient_address = users.blockchain_address))
     INNER JOIN tokens ON transactions.token_address = tokens.token_address
@@ -52,8 +52,8 @@ SELECT * FROM (
 -- name: account-latest-transactions-by-token
 -- Returns the first page of a users latest transactions, filter by token
 SELECT transactions.id, transactions.date_block, transactions.tx_hash, tokens.token_symbol, transactions.sender_address, transactions.recipient_address, transactions.tx_value, transactions.success,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.sender_address) as sender_identifier,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address) as recipient_identifier
+COALESCE((SELECT phone_number  FROM users WHERE blockchain_address = transactions.sender_address), 'SYSTEM') as sender_identifier,
+COALESCE((SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address), 'SYSTEM') as recipient_identifier
 FROM transactions
 INNER JOIN users ON ((transactions.sender_address = users.blockchain_address) OR (transactions.recipient_address = users.blockchain_address))
 INNER JOIN tokens ON transactions.token_address = tokens.token_address
@@ -62,8 +62,8 @@ WHERE users.phone_number = $1 AND tokens.token_symbol = $2 ORDER BY transactions
 -- name: account-latest-transactions-by-token-next
 -- Returns the next page based on a cursor, filter by token
 SELECT transactions.id, transactions.date_block, transactions.tx_hash, tokens.token_symbol, transactions.sender_address, transactions.recipient_address, transactions.tx_value, transactions.success,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.sender_address) as sender_identifier,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address) as recipient_identifier
+COALESCE((SELECT phone_number  FROM users WHERE blockchain_address = transactions.sender_address), 'SYSTEM') as sender_identifier,
+COALESCE((SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address), 'SYSTEM') as recipient_identifier
 FROM transactions
 INNER JOIN users ON ((transactions.sender_address = users.blockchain_address) OR (transactions.recipient_address = users.blockchain_address))
 INNER JOIN tokens ON transactions.token_address = tokens.token_address
@@ -73,8 +73,8 @@ WHERE users.phone_number = $1 AND tokens.token_symbol = $2 AND transactions.id <
 -- Returns the previous page based on cursor, filter by token
 SELECT * FROM (
     SELECT transactions.id, transactions.date_block, transactions.tx_hash, tokens.token_symbol, transactions.sender_address, transactions.recipient_address, transactions.tx_value, transactions.success,
-    (SELECT phone_number FROM users WHERE blockchain_address = transactions.sender_address) as sender_identifier,
-    (SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address) as recipient_identifier
+    COALESCE((SELECT phone_number  FROM users WHERE blockchain_address = transactions.sender_address), 'SYSTEM') as sender_identifier,
+    COALESCE((SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address), 'SYSTEM') as recipient_identifier
     FROM transactions
     INNER JOIN users ON ((transactions.sender_address = users.blockchain_address) OR (transactions.recipient_address = users.blockchain_address))
     INNER JOIN tokens ON transactions.token_address = tokens.token_address
@@ -84,8 +84,8 @@ SELECT * FROM (
 -- name: account-latest-transactions-by-archived-token
 -- Returns the first page of a users latest transactions, filter by token
 SELECT transactions.id, transactions.date_block, transactions.tx_hash, archived_tokens.token_symbol, transactions.sender_address, transactions.recipient_address, transactions.tx_value, transactions.success,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.sender_address) as sender_identifier,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_addres) as recipient_identifier
+COALESCE((SELECT phone_number  FROM users WHERE blockchain_address = transactions.sender_address), 'SYSTEM') as sender_identifier,
+COALESCE((SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address), 'SYSTEM') as recipient_identifier
 FROM transactions
 INNER JOIN users ON ((transactions.sender_address = users.blockchain_address) OR (transactions.recipient_address = users.blockchain_address))
 INNER JOIN archived_tokens ON transactions.token_address = archived_tokens.token_address
@@ -94,8 +94,8 @@ WHERE users.phone_number = $1 AND archived_tokens.token_address = $2 ORDER BY tr
 -- name: account-latest-transactions-by-archived-token-next
 -- Returns the next page based on a cursor, filter by token
 SELECT transactions.id, transactions.date_block, transactions.tx_hash, archived_tokens.token_symbol, transactions.sender_address, transactions.recipient_address, transactions.tx_value, transactions.success,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.sender_address) as sender_identifier,
-(SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address) as recipient_identifier
+COALESCE((SELECT phone_number  FROM users WHERE blockchain_address = transactions.sender_address), 'SYSTEM') as sender_identifier,
+COALESCE((SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address), 'SYSTEM') as recipient_identifier
 FROM transactions
 INNER JOIN users ON ((transactions.sender_address = users.blockchain_address) OR (transactions.recipient_address = users.blockchain_address))
 INNER JOIN archived_tokens ON transactions.token_address = archived_tokens.token_address
@@ -105,8 +105,8 @@ WHERE users.phone_number = $1 AND archived_tokens.token_address = $2 AND transac
 -- Returns the previous page based on cursor, filter by token
 SELECT * FROM (
     SELECT transactions.id, transactions.date_block, transactions.tx_hash, archived_tokens.token_symbol, transactions.sender_address, transactions.recipient_address, transactions.tx_value, transactions.success,
-    (SELECT phone_number FROM users WHERE blockchain_address = transactions.sender_address) as sender_identifier,
-    (SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address) as recipient_identifier
+    COALESCE((SELECT phone_number  FROM users WHERE blockchain_address = transactions.sender_address), 'SYSTEM') as sender_identifier,
+    COALESCE((SELECT phone_number FROM users WHERE blockchain_address = transactions.recipient_address), 'SYSTEM') as recipient_identifier
     FROM transactions
     INNER JOIN users ON ((transactions.sender_address = users.blockchain_address) OR (transactions.recipient_address = users.blockchain_address))
     INNER JOIN archived_tokens ON transactions.token_address = archived_tokens.token_address