A cancellation request will not help you here.
If eBay have removed the listing for some selling regulation breach, you need to reach out to them now for help with your refund. The seller may well have received a selling account restriction which means they cannot use their account at all, for ** days of the restriction.
This is the easiest and quickest way to contact eBay Customer Services, for a Call Back option.
https://www.ebay.co.uk/help/eua?id=5275&mkevt=1&mkpid
Lines open for ' live agents' 8 a.m. - 10 p.m. on weekdays
9 a.m. - 6 p.m. on weekends.
Automated agents will be available on chat outside of the above hours.
I recommend contacting CS first thing in the morning as there's more chance of Dublin answering.
@warne-905