500 internal server error setting up a paid account

[arctic iris]

Double checked everything. It's all correct.
This has been happening for months. I've contacted staff and have not received a response for weeks (understandable).
There seems to be no indication of what is wrong.
Has anyone had this issue before? And if so what could be done to resolve it?
Thanks!

Got a 500 in the console if it helps

I'm trying to set up a paid account as an individual

500 internal server error setting up a paid account

[wind panther]

This looks odd, this issue can be better resolved by contacting [e-mail]