I found this on the IRS website:

If you have questions about how to create an account, see Secure Access: How to Register for Certain Online Self-Help Tools.

Imagine that! And...it includes a section to expand, worded as:

Help with Common Issues

If you have issues registering or logging in to IRS online services, try the steps below.

This is going to get especially crazy with the new advanced child credit issue requiring registration to opt out.

Please note this is a Software Users Group, and not a Tax Help portal. It's a discussion forum for how to use the ProSeries Tax Preparation program. if you are not asking about using that program, on your Computer, you are Lost on the internet.