Bad service... and contract breach

Hi... Not Happy at all! May 2017 i was due for upgrade,i first went on the vodacom app for upgrade,a lady called me... and said there was only Samsung S7 available,so i said,ill rather go to vodacom shop,she then dropped the call.i went to Vall mall vodacom shop vanderbijlpark.took the Samsung S8 with Gear 3 Frontier. and a few days later i recieved the Handset(This one im using now) & about +- 2/3 months later they called me to go collect my Gear 3 frontier! so the agreement of contract was signed on May 2017. now i went to upgrade they say i can upgrade but need to pay this handset up until october 2019,they say thats when i got this contract.i went home got slips i recieved with this handset took it back to them to show them it was on may 2017. and stil the same storie. from the date signed on contract as upon agreed to...i already have this handset 24months. if the sales people failed to submit the contract same day,not my fault,its actually *****. its signed may 2017 but its shows october 2017 when it shows on the system.that was to agreed on by us. My mother have allot of contracts with vodacom...and after this we are not happy with the situation and customer care we got from them. This number is ********** 277. account holder charmaine van zyl ********** 519 thankyou