Can't make changes to build

Hello, ive never posted here before but i am desperate. I think this is the issue i'm experiencing. I cant build or delete anything in build mode, i cant save or exit the game when this glitch happens, & it often freezes my entire computer until i can restart. I've tried EVERYTHING, i've gotten rid of mods, ive started a new file, i've repaired the game, i've deleted the cache. It seems to happen regardless of lot, sim or save & i cant pinpoint what causes it, i think maybe placing walls or stairs. I have so many builds i worked so hard on that i want to save, & if i can't play with them anymore i'm going to just stop playing entirely, since it's genuinly broken. If anyone has ANY advice short of starting a completely new sims 4 game, i'd be very happy to hear it.