I haven't seen that particular error, but the general recommendations I would make would be to try another browser (or try it in the mobile app) and if you succeed there or can't do that, clear your cookies and log out and back in. Any number of possible reasons, some on eBay's side (which you can't fix, and reaching out to customer service is rarely helpful with things like that other than to get the issue on their radar) and some possibly on your side which you can try to address. Good luck!
