I recently stumbled apon a bug where when yomu go in the future and try the "check real estate" interaction, be it with the phone or with the computer, the interaction fails and the sim resets.
I found traces of this bug here (where the person mistakenly thinks it's somewhat normal) and here, where they believe it's related to the Awesome mod (which it is not, since I had the bug without ever installing it). I myself first believed it was related to Nraas Overwatch (but it's not).

Actually the bug is very simple : if you own any Residential, Building or Venue lot in the present, everything works fine, but if you own even one Resort (like the ones from Isla Paradiso), the Real Estate Manager will glitch in Oasis Landing.
The good news is, it's not permanent. Selling the resorts and going back to the future (lawl) re-enables the Real Estate Manager.

I'm posting this not to request help but to help people who might stumble apon this glitch in the future (lawl x2).