Are these unpaid seller fees from a long time ago? Seller fees are now taken immediately an item sells and not through a monthly invoice.
eBay Manage Payments now, have you registered for this? All sellers have to, to be able to list items for sale and receive payouts from those sales.
You need to provide eBay with details of a bank account and have this account verified. The usual method here, is for eBay to send 2 micro deposits into that nominated bank account for you to receive, and confirm to eBay.
Once this is completed, you will be able to list items for sale, and receive payouts from those sales.
This will show you how to register for eBay's Managed Payments.
https://www.ebay.co.uk/help/help/selling/getting-paid/introducing-managed-payments-ebay?id=4795
If there is an issue with the registration or this is a matter only for lon ago unpaid seller fees, contact eBay Customer Services, who have full access to your account, and can help you further here.
The easiest and quickest way to contact Customer Services is through this link, for a Call Back .
https://www.ebay.co.uk/help/eua?id=5275&mkevt=1&mkpid
On weekdays lines open between 8 a.m. and 10 p.m. - 6 p.m.
Weekends lines open between 9 a.m. to 6p.m.
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