diff --git a/app/Models/WalletAddress.php b/app/Models/WalletAddress.php
index 564832b..8268507 100644
--- a/app/Models/WalletAddress.php
+++ b/app/Models/WalletAddress.php
@@ -78,6 +78,11 @@ class WalletAddress extends Model
             if (! is_numeric($value)) {
                 continue;
             }
+            // A wallet balance can never be negative; clamp device-reported negatives to 0.
+            if ((float) $value < 0) {
+                $out[$col] = '0';
+                continue;
+            }
             $out[$col] = $value;
         }
 
@@ -99,6 +104,10 @@ class WalletAddress extends Model
         if (! is_numeric($amount)) {
             return (string) $amount;
         }
+        // Defensive: never render a negative balance (e.g. stale device-reported rows).
+        if ((float) $amount < 0) {
+            $amount = '0';
+        }
 
         $decimals = self::displayDecimals($coin);
         $formatted = number_format((float) $amount, $decimals, '.', '');