Extremely bad Cell C upgrade experience, struggling to reverse/change upgrade

On Friday the 30th of April I upgraded to a Huawei Nova 7, I was advised that google play services no longer work but was NOT advised at what extent google play services are required by almost all apps on the market. How cell-c can sell such a useless product on the market is beyond me. Regardless I kept my calm and I went back to the store and the manager was not present, she left early. I explained that the device is in pristine condition, with everything it came with, I also explained that the device appears to have a technical malfunction in certain apps with vertical lines on the screen. I then said that I want to upgrade to a different phone as I was not happy with my purchase, the store clerk said she cannot do anything as her manager isn't present, and instead told me to go and the manager will phone me back the next day.

The next day the manager phones me back, I explain the whole situation, including that I want to change the phone I want to upgrade to, after which she continually throws terms and conditions in my face, I explained that I want a more expensive phone that has google play services instead and she denied me any possibility of coming to an arrangement.

Tomorrow I am going to take the phone in for a technical inspection, as that seems to be my only route but nontheless I am currently not interested in being a Cell C customer any longer, as soon as possible I will make arrangements to cancel my contract and never do business with them again, I was calm throughout this process, I tried my best to come to an arrangement with Cell C and I'm appalled at how little the manager of the century city branch cares about customers.

She did not in the least seem remotely interested in making me as a customer happy, nor to help me in any way, honestly very disappointed.