NPCs won't spawn

Product: The Sims 4
Platform:PC
Which language are you playing the game in? English
How often does the bug occur? Every time (100%)
What is your current game version number? Most recent patch
What expansions, game packs, and stuff packs do you have installed? City Living, Get Together, Get Famous, Seasons, Parenthood, Vintage Glamour Stuff
Steps: How can we find the bug ourselves? Not sure
What happens when the bug occurs? NPC Sims will not spawn. If they ask to come over, they don't spawn when I accept. When they invite my sim places, my sim shows up, but no one else does, not the inviter, not fellow NPCs, not even service sims like the bartender. Services like maid/pizza delivery don't work. Stall workers don't show up. There is not a single NPC in the entire game
What do you expect to see? People in the town, especially the stall/service worker sims. People to come over when invited
Have you installed any customization with the game, e.g. Custom Content or Mods? Not now. I've removed them.
Did this issue appear after a specific patch or change you made to your system? Neutral/Not Sure 

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As it says, no NPCs are showing up anywhere in my town. I thought perhaps an out of date mod was to blame, but the issue persists even when all mods are disabled. I'm really not sure what to do at this point. It used to work fine, but broke at some point during the previous patch. I first noticed when an NPC invited one of my sims out - it went fine, there were plenty of other sims, she showed up, all was good. Then, she invited my sim out again, but no one showed up at the venue, not even the staff. It was completely empty except for my sim. And now that happens all the time when I go places. There are no NPCs at all. Has anyone else encountered this issue?

Edit: Worked it out, it was an issue with household size from master controller. Raising the total sim limit for lots fixed it