You can use your own delivery service but if you initially chose eBay postage then that tracking will be registered.
Using a laptop / PC and Chrome you should be able to manually edit / change those numbers if not, contact eBay Customer Services tomorrow morning they can change the tracking for you.
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 between 8 a.m. to 10 p.m. on weekdays.
9 a.m. to 6 p.m. on weekends.
I recommend contacting CS very first thing in the morning, when the lines first open, as there's more chance of Dublin answering.
@griffgleglen