I am unable to change my account type for my sandbox account. this link isn't working: https://scgi.sandbox.ebay.com/ws/eBayISAPI.dll?ChangeRegistrationAccountType&guest=1
as i am based in UK.
Please change TESTUSER_haynesx10 to Business.
I have also called the ValidateTestUserRegistrationRequest and it was successful, but no change.
the user is TESTUSER_haynesx10.
the dev user is haynesx