FIFA 20 beta not working seems to be the plight of certain members of the FIFA community. The overwhelming majority of the community has been positive about the beta launch so far, but there have been a few outliers.
If you're having problems with the beta working, you probably were not invited, tried to use a friend''s code or bought one online.
FIFA 20 Beta Not Working: Codes are Tied to Accounts
For one, make sure the time is live. The FIFA 20 beta went live at 12 p.m. ET Friday. So if you were trying before the time, that might be the reason. Another potential problem is the actual code. If you're borrowing a code from a friend or purchase one on the internet, the codes are locked to a specific account. You can't use it, even if it's an unused beta code.
The beta is only live in US and UK, so if you're connected to another server outside of those, that may be another reason why it's not working.
If you're legitimately dealing with problems, post on the EA FIFA forums as EA hasn't announced any issues with connection.
Photo courtesy of EA Sports