Keep phoning about a mtn contract

A month ago my WIFE was interested in the new iPhone X, so she went to mtn and app**** for one. They said she must wait 2 weeks, so we went to vodacom where she is and just upgraded there and have the phone quicker. She went back and told mtn she doesn't want the phone anymore and they canceled it at MTN in Somerset west mall. Now Van De Venter Mojapelo Inc is phoning ME to pay them because she canceled the contract!!!!! According to the consumer act we can cancel a contract and not pay anything because we never got the stupid phone!!!! Between them and MTN they are the worst people to deal with! Never ever have anything to do with these companies!