Did you use another label? Then, if using a PC / laptop and Chrome doesn't allow you to manually edit to the new tracking number you'll need the assistance of Customer Services to do this for you.
Currently there is an issue with contacting CS with this usual contact link below, try it but if it is still greyed out, then I have found a workaround described below.
https://www.ebay.co.uk/help/eua?id=5275&mkevt=1&mkpid
On your homepage, go top left click on Help & Contact.
Then enter your issue, I just entered ' Payout issue'.
Click on several boxes asking further questions and you will come to a left sidebar ... Contact Us >> Chat with Automated Assistant. I got through in seconds.
I'm using a laptop and Chrome.
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The above may help for the time being.
@sinbad123sinbad