Impossible to claim free Samsung accessory

After considering to port to another network for months now my wife upgraded her contract with MTN on Saturday purely for the reason that MTN promised a free Gear Fit2 Pro when you take the S9+ on contract.

We were told that we could claim the watch on the Samsung rewards app on the new phone. That did not work. We went back MTN the next day (Sunday). The staff could not help. The icon we were supposed to use to claim the watch had disappeared. They then told us that there was an alternative way of claiming it and forwarded us an e-mail which reads "You can claim your gearfit pro via emailing your NAME and SURNAME, PROOF OF PURCHASE, RESIDENTIAL ADRESS and CELL NUMBER too ********** My wife did this but the email failed because the email address does not exist.