Advice needed

Hello Reddit!

So I bought off Dream like 3 weeks ago, just before this whole frenzy happened. My package came, but here's where I need your collective input.

It's currently waiting at the post office. It's been marked "held for pickup by sender" which meant I had to go grab it myself. Whatever. I go, hand over my notice, but they won't give it to me because I wrote the shortened version of my name (which I use exclusively, as I'm transgender), while my driver's license has my full name. They want me to contact the vendor and get me to change my name somehow.

What do? I was thinking of bringing my tenancy agreement with me (because she kept saying "we don't know, ___ could be a boy"... no kidding, lady), but after this paranoia explosion about the market I'm wondering if I should just let it go. I contacted the vendor I bought from, whose reviews span positive up to 4 days ago, and she's always delivered in the past. I'd rather not let ~100 in merch go because I let my paranoia get the best of me, but I'm just a little sketched and/or confused.

EDIT: I've ordered other packs in the exact same way with no issue, this is the first one that I've had to go pick up. I guess until my proof of name change comes in I gotta just suck it up and use my full name.