No delivery and now the contract package has changed

My mom upgraded her contract on the 24th November 2017 on Black friday taking a Samsung J5 Prime for R99pm and a week later she was called and told delivery will be done in the next two days but they will call her 1st to make sure she is home for the delivery. They delivered the next day without calling and my mom wasn't home and they returned with the phone and told my mom they will deliver again but to this day no delivery has been done. We decide to call Vodacom today to find out what's going on and we were told the phone has been returned to the warehouse and they will have to process the upgrade again but now the contract for the same phone will be R199pm. How is that fair. Its not my fault that they never called me to make sure I am home for the delivery. I want my phone with the same amount I upgraded on Black friday. My number is ********** I really hope they can sort this out for because its not fair that now the contract is double the amount that what I initially app**** for