Double billing of handset amount

My cellphone contract was with Nashua Mobile until they went out of business. I was informed by both MTN and Nashua Mobile that my contract would be taken over by MTN (and it would have no impact on me).<br> <br> I recently upgraded my contract with MTN and now they are double billing me for the handset. The reason according to them is I still owe Nashua for my handset. However this makes no sense. My contract was TAKEN OVER IN ITS ENTIRITY. Also when I upgraded no-one informed me that I would be double billed. What is also concerning is MTN cannot inform me when I will stop being double billed. <br> <br> My argument is that when MTN took over my contract they did not inform me in writing or verbally that I would still owe Nashua Mobile the remainder of my handset fee. They also did not inform me of this when I upgraded. If a separate amount of money was being debited from me by Nashua I could MAYBE understand that but both FEES are being paid to MTN. <br> <br> If Nashua still existed and I had upgraded at 20 months as per usual this wouldn't happen so if my contract has moved why is it different?<br> <br> This is just another example of MTN doing what they want without informing their customers.