diff --git a/app/lib/actions/locationActions.ts b/app/lib/actions/locationActions.ts
index b689453..d9a5be9 100644
--- a/app/lib/actions/locationActions.ts
+++ b/app/lib/actions/locationActions.ts
@@ -630,6 +630,17 @@ export const uploadUtilBillsProofOfPayment = async (locationID: string, formData
     noStore();
 
     try {
+
+        // check if attachment already exists for the location
+        const dbClient = await getDbClient();
+
+        const existingLocation = await dbClient.collection<BillingLocation>("lokacije")
+            .findOne({ _id: locationID }, { projection: { utilBillsProofOfPaymentAttachment: 1 } });
+
+        if (existingLocation?.utilBillsProofOfPaymentAttachment) {
+            return { success: false, error: 'An attachment already exists for this location' };
+        }
+
         const file = formData.get('utilBillsProofOfPaymentAttachment') as File;
 
         // Validate file type
@@ -643,8 +654,6 @@ export const uploadUtilBillsProofOfPayment = async (locationID: string, formData
             return { success: false, error: 'Invalid file' };
         }
 
-        const dbClient = await getDbClient();
-
         // Update the location with the attachment
         await dbClient.collection<BillingLocation>("lokacije")
             .updateOne(