Position Modifier not working correctly

I've been working on an EA for a while and part of it adjusts the stop loss on positions based on other criteria. The opening conditions allow it to open up to 4 positions at a time, all the buy orders are set with the magic index of 4 and sells are 3.

For some reason the stop loss adjuster is working fine but only on the first position, the other 3 are not being modified at all.

This is probably me with smoke kind of rookie error but if anyone has any ideas that might be able to solve this issue that would be amazing.

Thanks

Tom

Is there any Error code ?
 Are you sure your value for SL are correct ? It must be :
StopLoss_BUY = OrderOpenPrice() - Distance;
StopLoss_SELL= OrderOpenPrice() + Distance;
Where Order must be Selected before,
and Distance must be greater (>) than
MathMax( MarketInfo(_Symbol,MODE_STOPLEVEL), MarketInfo(_Symbol,MODE_FREEZELEVEL))*_Point;

Here we go, all orders with magic xxx are modified - similar tp.

   void PairLossModify(){
    bool modifypairloss;
    for(cnt=OrdersTotal();cnt>=0;cnt--){
      if(OrderSelect(cnt,SELECT_BY_POS,MODE_TRADES))
      if(OrderSymbol()==Symbol() && OrderMagicNumber()==Magic){
         if(OrderType()==OP_BUY){
            if(OrderStopLoss()==0 && MaxPairLoss!=0){
               RefreshRates();
               modifypairloss=OrderModify(OrderTicket(),OrderOpenPrice(),NormalizeDouble(Ask+MaxPairLoss*pt,Digits),OrderTakeProfit(),0,Red);
            }
         }
         if(OrderType()==OP_SELL){
            if(OrderStopLoss()==0 && MaxPairLoss!=0){
               RefreshRates();
               modifypairloss=OrderModify(OrderTicket(),OrderOpenPrice(),NormalizeDouble(Bid-MaxPairLoss*pt,Digits),OrderTakeProfit(),0,Red);
            }
          }
        }
      }
    }