Postmates not honoring offer

Did anyone else have issues with the offer of getting rewarded after signing up and making your first order with Postmates that was offered about 10 days back? I fulfilled the offer about 16 days ago and I've been emailing Postmates support all day and they just eventually said "it seems this offer has come from a third party website so we cannot honor it. Have a nice day."

Swagbucks says they can't help me without screenshots of the email that was supposed to be sent "confirming I was enrolled in the offer" but the swagbucks link sent me a text to my phone to sign up with that, so I never got such an email.

Is there anything I can do in this situation? Or am I just supposed to eat the cost of an extremely overpriced Pizza (BTW I heard on the postmates reddit that the postmates website just overcharges you just to make sure the order goes through and then they eventually replace that with a smaller charge. That never happened with me either, they are still charging me the full 13 dollars for a pizza that normally costs 8, not including service fees and other fees)