Sims 4 Crashing and Lagging

When i open the game it runs for about 5 minutes before it starts lagging. I've done everything I know how to do and was wondering if anyone has any advice. Undownloaded and redownloaded both the EA App and the Sims game as well. It takes like 12 hours in the game to complete simple tasks and also crashes on me within 30 minutes to 2 hours of playing. If anyone can tell me what I'm doing wrong that would be great!