Wasted money on some "nice" panties!!

I bought 2 sets of panties, which were labeled on the hanger as L(arge) which I didnt doubt, then when I got home I noticed it wasn't large they were medium. I didnt take of the tags or take them appart (they were of course in a set so they were attached to each other) or try them on. So I havent worn it yet, and wanted to simply terurn them to thw store just to swop them for a larger size.

You cannot try them on in store, so I trusted that Ive bought large before it fits... this should fit. But it was labeled wrong...

Contacted support through email... no response, tried through the app... no repsonse, took forever so I tried to contact them through whatsapp which finally put me through to someone which said no problem call this number to speak to the manager and they'll sort it out... called that number which didnt give an option to speak to a manager, just to customer service which was a bit sour and adamant it can't be returned no matter what... and I spent quite a bit on those 2 sets... cant return refund or exchange it... and they mislabeled it. Now its just my problem?

I understand that its not hygenic to exhange underwear... but, its clearly not worn the tags, its attached how should i have put them on with everything still attached. Its ridiculous!!! Wasted money on 2 sets, which wouldnt fit me which is clearly not worn. And can't be worn.