Wrong Phone

I app**** for a Samsung A33 contract phone a week an half ago. Everything went well in almost half hour of approval.Yesterday the courier came with the package.. Just to find out it was a wrong phone Samsung AO4e in disbelief i open cellphone. After that I phone Mtn several times and emails with no luck, i went to my local Mtn shop they didn't even bother taking the phone just tell my that i must contact Mtn than they must send email to my phone for them to accept it. So today i phone again several times and emails with a bit of luck i just get a reference nr nothing else. So am sitting with a phone i dont want and i really needed a phone for work related,and i refuse to pay end month. Hope someone can help me.