The official support had replied to me the day after this fixed itself for me and advised it’s often corrupted cookies causing this problem. You could try clearing your browser cookies to see if that works.

I thought maybe it was a new member issue as well, but I just tried placing the bid again 30min ago and it worked no problem.  So I'm guessing there was a backend issue with the bidding/validation system for a period yesterday.

I have also tried Chrome, Safari, and Firefox desktop browsers with no luck...

I've tried both phone and desktop, and desktop incognito mode.  Same error. Listing number is:  5695262292, and same error for 5706773907 before it closed and reset (and still has the same error now that the auction close date has bumped a week out).