Cellphone contract mtn / mondo

In October 2022 my daughter bought an iPhone 14 pro max from Mtn online store apparently called mondo (online services provider for mtn) upon Delivery she noticed that they sent a wrong colour and she immediately contacted mtn which they referred her to mondo and advised her to send the phone to any mtn store around her radius, none of the mtn shops or wanted to accepted the phone and advuse her its online order therefore they will not accept the phone she needs to contact mondo, she then contacted mondo and they had said they will arrange collection

On the 24 October 2023 DSV courier driver name N Neville collected the phone and send it back and the consultant at Mondo advised her that they won't be able to change or straight stop the phone or the colour she will have to cancel the contract, she then canceled the contract

Now the problem is even though they canceled the contract and collected the phone they kept on debiting her account for 2 months already and they now sending the letter of collections and it affecting her credit negatively, I think mondo are **** they had the phone and the collecting the funds after they canceled the contact I need this to be sorted out between them and mtn and remove her name on the credit institution asap, should I don't get any response on this Regards I will then take a further step

I will would like to advise anyone who might be interested in applying for cellphone contract via online throught mondo /mtn please don't, run for your life they ****ming people with online thing or they simply don't know what they doing