Shocking service at upgrade time!

More shocking service from MTN at upgrade time. Went into MTN Dainfern store on Black Friday to upgrade my 2 accounts. After spending almost an hour there, i left the store thinking both were sorted. I get my statement today and it shows only 1 of the accounts were upgraded and for the other one i am paying the full month to month price. I phone the call centre and get told I have to go into the store to sort out. I go into the store and get told I need to go to head office in 14th Ave to sort out. And that the Black Friday upgrade is now not available! They have made their system and process issues my problem and inconvenience! And this after being a customer for almost 20 years!