diff --git a/handlers/application/menuhandler.go b/handlers/application/menuhandler.go
index 6012818..4644543 100644
--- a/handlers/application/menuhandler.go
+++ b/handlers/application/menuhandler.go
@@ -601,16 +601,20 @@ func (h *MenuHandlers) ValidateBlockedNumber(ctx context.Context, sym string, in
 		return res, fmt.Errorf("missing session")
 	}
 
-	if h.st.Back() {
+	if string(input) == "0" {
 		res.FlagReset = append(res.FlagReset, flag_unregistered_number)
 		return res, nil
 	}
+
 	blockedNumber := string(input)
-	_, err = store.ReadEntry(ctx, blockedNumber, storedb.DATA_PUBLIC_KEY)
-	if !phone.IsValidPhoneNumber(blockedNumber) {
+	formattedNumber, err := phone.FormatPhoneNumber(blockedNumber)
+	if err != nil {
 		res.FlagSet = append(res.FlagSet, flag_unregistered_number)
+		logg.ErrorCtxf(ctx, "Failed to format the phone number: %s", blockedNumber, "error", err)
 		return res, nil
 	}
+
+	_, err = store.ReadEntry(ctx, formattedNumber, storedb.DATA_PUBLIC_KEY)
 	if err != nil {
 		if db.IsNotFound(err) {
 			logg.InfoCtxf(ctx, "Invalid or unregistered number")
@@ -621,7 +625,7 @@ func (h *MenuHandlers) ValidateBlockedNumber(ctx context.Context, sym string, in
 			return res, err
 		}
 	}
-	err = store.WriteEntry(ctx, sessionId, storedb.DATA_BLOCKED_NUMBER, []byte(blockedNumber))
+	err = store.WriteEntry(ctx, sessionId, storedb.DATA_BLOCKED_NUMBER, []byte(formattedNumber))
 	if err != nil {
 		return res, nil
 	}