'SymbolInfoDouble' - no one of the overloads can be applied to the function call

how can i solve this

sohorab hossain:
how can i solve this

Next time, post your code not as screenshot, but properly, by using the >Code-Button<.
  1. Never show your code as a screenshot. Insert it properly in your post using the CODE button (Alt-S).

    Code button in editor

  2. The property SYMBOL_DIGITS returns an integer, not a double. Use SymbolInfoInteger() instead.