We've all had it happen, you win a match but the other person got disconnected, or the game glitched. Ether way your out your stars, energy and the win. Here is what works for me running the latest IOS on a 5S.
As soon as this happens, exit the app completely and restart. All rewards will be restored.
Only time it dosn't seem to work is when the "unable to find an opponet" glitch happens.
Hope this helps others😉
Ya ought ta know better than to mess with another mans hat