LondonRihanna Did you ever move the entire Sims 4 folder out of Documents > Electronic Arts? If not, please do so now, and don't add anything (saves, mods, Gallery items, etc.) to the new folder. Test a new save first and see how it goes. If it's fine, you can copy over an existing save and test that too, still with no mods or custom content.
If that doesn't or didn't help, I'd like to see your dxdiag. You can attach the full report, saved as a .txt file, to a reply here. Use the camera (Insert Media) icon included with the other formatting options.