PROBLEMS with reversal of Up Grade

Original call in June 2019 to confirm if contract is on pay as you go, confirmation was yes but they asked if i would upgrade- My response was NO as we have wi-fi and upgrade is not needed. then i was asked to reduce my contribution and i eventually agreed but changed my mind. With the change they tried to do they put me on another 2 year contract which i did not want. I have been struggling since June 2019 to cancel the rest to remain on pay and you go. NO SUCCESS