i had the same problem with annualcreditreport.com
When I try to pull a free transunion or equifax it always fails. I only managed to get my free experian report from that site
Nothing is wrong with your identity or with the credit bureaus
the annualcreditreport.com is an independant company who provides this service.
It can be they don't have enough information about you to confirm your identity. Like not enough Credit Lines, or recent inactivity...
You can try and call them, but it's hard to get a human on the line
try
877-322-8228
If you find a solution let me know how you managed that
Starting Score: EQ 683 TU 714