Upgrade nightmare

I have multiple contracts with Vodacom. One of my contracts (the main number) was upgraded in April (successfully and no issues). One of the other contracts was due for an upgrade and we upgraded this number in November 2023 via the online system. We have received the devices per the contract and then on the 1st of December we became aware that they put the new contract on the main number that was already upgraded earlier this year. After phoning the online care centre, they informed us that the only way to reverse this was if we return the device to them. Which would have been fine, but everything was already transferred to the new phone and we put on a screen guard and everything. I don't know how the system even allowed them to upgrade a number for a second time in this year.