@Xemisa2World there is an open bug report for Off Grid lots in our bugs section here:
I can't find an open bug report for the mold challenge with the exact problem you describe but you can start a new one in bug reports, here's the index for you.
https://answers.ea.com/t5/Bug-Reports/bd-p/The-Sims-4-Bugs
You might have done one before but if not, just select New Topic. It should prompt you with a bug template to fill in. It's important to list your packs (or the ones you don't have if you have most of them) so they can replicate it. Also explain that you've already been through console troubleshooting.
There are issues with the mailbox with the Reaper Event and they are testing a fix that could be rolled out soon, in fact I think we can expect a few fixes for the event soon but there's a tip from EA to replace your mailbox with the "Ol' Rusty Mailbox". You can try that if you want to. The other bugs for the Reaper Event are here:
Hope this helps.
