Modify button

 

Sometimes I am unable to modify an order that I placed. 

Please assist with this

 
Maybe the levels are too close have you tried to widen the gap ? 
 
  1. Do you really expect an answer? There are no mind readers here and our crystal balls are cracked. Always post all relevant code (using SRC).
         How To Ask Questions The Smart Way. 2004
              Be precise and informative about your problem

    We can't see your broken code.

    Fix your broken code.

    With the information you've provided — we can only guess. And you haven't provided any useful information for that.

  2. You can't move stops (or pending prices) closer to the market than the minimum: MODE_STOPLEVEL * _Point or SymbolInfoInteger(SYMBOL_TRADE_STOPS_LEVEL).
              Requirements and Limitations in Making Trades - Appendixes - MQL4 Tutorial

    On some ECN type brokers the value might be zero (the broker doesn't know.) Use a minimum of two (2) PIPs.