I have had an old account that I have lost the details of, however, it still has my custom domain assigned to it.
I have tried to contact support twice without any help resolving it, the first time I got a response saying it was fine and not understand the problem, it might have been my fault if I wasn’t clear enough and the second time I have been completely ignored.
I need to change this over and it’s frustrating that I am unable to change it myself and that support is just ignoring my requests for help.
Welcome to the forums. No one is ignoring your request there is no SLA for customers on a starter tier. We work as fast as we can for all of our users to get a response. Forums response time is between 2-3 days.
Now to your question-
What is your domain you are trying to add to your new account? You’ll need to verify your domain ownership please follow the instructions here.