oscarli

I tried to register for self assessment, and it asked to check my identity (to enter my full name, DOB, and my NI number). However after I entered these details, it returned: Unable to verify your identity Sorry, there is a problem with the service Try again later. I have the NI number on the payslip from my previous job, so this cannot be wrong. I have tried multiple times, same result. I also tried "forgot NI number" and it asked me to enter my postcode, but same result as well. I have not changed address since I got my NI number. Before this, I already verified myself using GOV.UK Verify (uploaded passport, driving license etc). Is there anything else I can do? Or who should I contact to address this issue?