OrderModify Error 130, Stop is valid, but it does not work

Hi experts,

I create two EAs 1 for Long of currency pair EUR/USD and 1 for Short of EUR/USD.

So, I create a method, that should change every ten minutes the StopLoss. However, for the Short-side it works, but for the Long-Side I

get always the OrderModify Error 130. I do not understand why? I use the following code snippet which should solve this issue:

Thanks for your support,

Hoschie

               calc = (Long.stop / 100) * 0.01;
               myDigits = MarketInfo(Symbol(),MODE_DIGITS);
               Long.stop = NormalizeDouble(Long.stop + calc,myDigits);
             if( (OrderModify(Long.ticket,OrderOpenPrice(),Long.stop,OrderTakeProfit(),0,White)))
             {
               lastMove = TimeCurrent();
             }
             else
             {
                bBuyPos = false;
                Alert("orderModify failed: ", GetLastError());
             }