I ordered an item from website ioffer.com and the seller provided me the following tracking number: RC295575572CN (I live in Spain)

The purchase was supposedly delivered on May 19th but I didn't receive it, so I went to my local post office and they told me the seller probably gave me the wrong tracking number since the item "RC295575572CN" was correctly delivered somewhere else.

I'm not allowed to contact the seller anymore so I'd like to know if there's a way of knowing what's my real tracking number - and where the item is since it was definitely not delivered here. I'm certain I provided the right shipping address.

Even though I had the right tracking number, the item wasn't delivered so I guess there must be a problem with chinapost.

Thanks!