"You can add people using an iCloud account email address with Home enabled." error

Hi, i want to add my folks to my home, but it doesn´t work. I get the "You can add people using an iCloud account email address with Home enabled." error, the other devices is sign into iCloud (with family sharing) and has enabled Home on iCloud.

To information have i recently been a publicly beta tester, but deleted my account when i figgured it might be the reason why it didn`t work.

Have no clue what to do, so please help me.

[Re-Titled by Moderator]