I ran two trips for the gift (double ear pottery p...

I ran two trips for the gift (double ear pottery pot). After spending 300 yuan on the first trip, I was told that the pottery pot was gone. I only got the exchange voucher. At the end of July, I could get the voucher to exchange for the pottery pot.
When I came to exchange for the second time, I was told that the binaural pot "cannot be heated or cooked."
Can't a pot be heated or cooked? Then why is it called a pot? Why doesn t the DM tell me?
I'm not reconciled after running twice, but it feels really bad!