After updating realms to 1.16 by making a back-up, deleting the nether files in a singleplayer version and reuploading the world again my (free trial of) realms gave an overflow error multiple times (after loading the nether with all 5 people online being kicked out). After that my game chashed a view times when i tried to re-open realms in general.

When i go to my minecraft.net account my (free trail of) realms is gone and it has the screen with where and how to buy realms again.