I have noticed it has got weird patches on the trunk, that look like the barks lifting off and theres white stuff coming out from underneath. I touched it and the white stuff was kind of cottonwoolish, and dry. It also looks shiny on top of some of the leaves and ive seen one black fly under one leaf. I have took some photos of it. If anyone can help me it would be hugely appreciated!! 
Link to the album with the pics in .. https://img41.imageshack.us/g/maple8.jpg/[/img]