Sims in a relationship say they’re single

I literally had this issue yesterday and somehow fixed it today. I had restarted my game many times, ended up evicting the household because it was bugging out. The two sims had already gone through the works of dating and asking to be partners, even exchanged promise rings, and all of a sudden on their Christmas, it showed they weren't dating even though they were. I tried to just make them date again and the option "ask if single" was the only option available, along with the regular flirting and such. After selecting that, it did not pop up to ask to be gf or bf. So, after evicting and making a whole new household, it was still buggy. So I deleted the new household all together, went to the previous original household, copied it into my gallery, deleted the existing "not placed in world" household I had evicted, and then closed the game after saving. Gave it about 5 mins to stay closed, opened the game again, and hit start NEW GAME. The create a sim opened to make a new household, I went in to the gallery and selected to use the copy of the og household, "are you sure you want to replace this household blahblahblah", yes, and then went and placed them in a house. Their relationships and such reset like they were new sims, but their skills carried over surprisingly and even their New Years resolutions and school grade (i was tinkering alot trying to fix without deleting first, they are teens), cool bonus, and it fixed the issue. All I had to do was rebuild their relationship. I hope this helped, if not you, then someone else who's having these issues too. And so far my 'new' game is running smoothly.