I've accidentally dropped my iPhone 6, the display glass is cracked but it still works fine. Except when someone calls me it always drops the first call like if I'm already talking to someone. It never shows me the first incoming call, I only see a missing call post factum. Although when the same person calls me again right after I get the call. Is it possible to fix this? Perhaps I just need to replace some module (e.g. the one which reads the sim card).
I don't have an official Apple service at my location.