On your phone only (not a laptop or PC) you can ring them or request they ring you. So view this link on your phone: https://www.ebay.co.uk/help/eua?id=5190
Or if you explain your problem someone on here may be able to help.
You do realise that you do not buy from ebay and if you are dissatisfied that there are means of you dealing with sellers without speaking to ebay! Suggest you read the 30 day money back guarantee, there is a link on the right side of every listing.