fix edit receipt purchase

internal/modules/purchases/repositories/purchase.repository.go

@@ -169,6 +169,7 @@ type PurchaseReceivingUpdate struct {
 	TravelNumber          *string
 	TravelDocumentPath    *string
 	VehicleNumber         *string
+	ClearVehicleNumber    bool
 	ReceivedQty           *float64
 	WarehouseID           *uint
 	ProductWarehouseID    *uint
@@ -246,6 +247,8 @@ func (r *PurchaseRepositoryImpl) UpdateReceivingDetails(
 		}
 		if upd.VehicleNumber != nil {
 			data["vehicle_number"] = upd.VehicleNumber
+		} else if upd.ClearVehicleNumber {
+			data["vehicle_number"] = gorm.Expr("NULL")
 		}
 		if upd.WarehouseID != nil && *upd.WarehouseID != 0 {
 			data["warehouse_id"] = upd.WarehouseID