Lots disappear when I travel to them

Whenever i decide to travel to a lot that isn't a residential, the lot disappears. for example i travelled through the phone like i always do but when i got to the park in Brindleton bay it was not there. i then exited to manage worlds and it told me "this lot is not available". the same happened when i held a group meeting for the paragons but when i got to the place they always hold the meetings, it wasn't there. i don't know what is happening!!! i don't use any mods or cc so it couldn't be anything to do with that. can someone please help me.