Can't access eBay, suspect Firefox but not sure

Hi, I'm still using Windows 7. Yes probably that's a cause but I'm not sure how. I'm using Firefox 115.38.0esr. Now for a while I've been finding it difficult to log into eBay. I'd try and log on and get this message "SORRY Something went wrong on our end <a varying error number> Please go back and try again or go to eBay Homepage." I'd go to the homepage and successfully log in. Then it took more than one try. Now I can't log in at all. I can still log in on a buying only account. It doesn't allow me to use the password, but it will accept access via text message. With the seller accounts, it doesn't give the option for access via text message only. Can this be fixed by Mozilla? I removed all extensions, and reset by PC to an earlier backup in case corruption was a cause. I've also deleted the cash.