Realms 1.13 After update a new resourcepack appeared in the list

After the last update, my realm looked weird. It appears there is a recourse pack active. One that I never purchased. When trying to deactivate it, the game throws an error stating something like I don't own this pack, "purebdcraft", or parts of it. I can't get rid of it!

Also tried to replace the world which resulted in an error too. The error was not specified.