Sims 4 World Reset

I've been playing this one household on one save for a while now and for some reason, everything was removed. I was working on a separate household in Brindlewood Bay on the same save then when I went back to the original family in the starter world, it was all reset. The family was gone, the house they were in was back to the premade version, and their previous homes in the same neighborhood were also back to their premade version. The new household I made was fine but I don't know how to get back my original family. I bulldozed the premade house and put down the home I built and I naively went to the gallery to put them back but all of their money is gone and they can't even afford the house. I don't know what to do. I looked up how to roll back the save but it isn't looking like it's working. I also don't want to just give them simoleons using cheats because the whole point of their lineage was to complete all of the Xbox achievements and obviously that would disable it.