Great game but needs fixing

1. Keeps crashing in middle of fights.
2. Lags a lot.
3. I never get the rewards from the faction wars until Ive closed the app and restarted the game.
4. Sometimes it will say connection error when my wifi is working perfectly.
5. Clarification needed: can I not level up my account past level 51? And do all characters stop levelling up at 50?

Bubzisback about Mortal Kombat, v1.8