I'm having the same problem too. I play on PS4 and have no mods or CC. Everytime I leave my lot and come back, all my doors have somehow become unlocked. When I clock on the door, it appears that the lock is still in place (one of the options that shows is "Unlock"), but random sims are able to walk through the doors.
Every time I come back I have to click on each door, click unlock, and then reset all my settings to the way I want them. Once I do that then sims I want to stay out are no longer able to enter through the doors.
Very frustrating as I have quite a few doors that I have to reset each time. It certainly makes me want to travel less which is frustrating because I feel like I'm missisng out on a huge part of the game this way. I hope there can be a solution to this glitch soon
