diff --git a/app/ninja/repositories/PaymentRepository.php b/app/ninja/repositories/PaymentRepository.php
index c10acb68c6ea..19535f3352f5 100755
--- a/app/ninja/repositories/PaymentRepository.php
+++ b/app/ninja/repositories/PaymentRepository.php
@@ -68,7 +68,7 @@ class PaymentRepository
         $rules = array(
             'client' => 'required',
             'invoice' => 'required',
-            'amount' => 'required|positive',
+            'amount' => 'required',
         );
 
         if ($input['payment_type_id'] == PAYMENT_TYPE_CREDIT) {