Did somebody send me something?

I received a little grey baggie envelope this morning with a British “1st” logo on it. I only briefly saw the sender, it looked like it said “pearl” or something like that.
The reason I ask is because the envelope was empty (so I gave it back to the postman).

The only thing like that that I’m expecting is coming from China (in half a month) and stuff from the DWP to do with mom’s pension which I would imagine would come in a regular envelope.

So, just asking if anybody here sent me anything?