im seller, buyer started return req, issued packlink return, parcel now missing, cant get req ref id

[digitalreload]

I sold an item, buyer advised not working and wanted a return/refund. After comms, I've provided a return label and went with ebays own packlink (appreciate this was probably a mistake) with ebay support telling me I'd be covered through them.

The item though has been returned/delivered as to the royal mail tracking, but not to me (was in and have cctv). Went to the royal mail depot and they advised it went to a different address not to far from mine (a health centre).

Tried to go through ebay CS, and they advised to make a claim through packlink (lost item) but I dont have the  packlink ref number. Trying to find it throuh their lookups is not working. Asked the buyer if they have it but they havent been responding on that

The return does not appear on here: https://delivery.ebay.co.uk/private/shipments/all or on here: https://delivery.ebay.co.uk/private/shipments/all , and I cant find any way to contact anyone at packlink direct or through webchat without  first having their reference number

Any help appreciated

[roger_roger_over_and_nowt]

Have you checked at the health centre ?.

[digitalreload]

yes, they dont have any items of that size/weight (big box, 2kg), they have some smaller items (packets and small parcels), but not under my name. Given the packlink label im not even sure how it would get there, but assuming it did it could be also under another name (some sort of complete postal failure?), but didnt feel like they wanted me to go through all their smaller items of post