[Open] Disappearing contacts and relationships of Sims

This just started happening to me this week. Out of nowhere, all my Sims were missing several contacts. Ranging from new contacts to old. Some are other players' Sims that they interact with each day, and I can no longer summon them or find them in the contacts page.

No missing relationships this time, thankfully (only one that went missing a few months ago after I made a Sim passive). I hope there can someday be a way to get these missing Sims contacts back.