Forcing to upgrade to new device contract

*** I need to upgrade/renew my contract from a normal new device (Samsung Galaxy S10) + Airtime & Data to a Sim Card contract-I require 10GB Anytime in my package. I went to MTN Store in Karaglen Centre in Edenvale and after 45 minutes I stormed out of the store with nothing achieved. They are making it so difficult to renew to a SIM Card contract. I now need to buy a Mobile Router, otherwise I cannot do phone calls- I need a new Sim Card (This one I thought was reasonable) BUT after waiting 45 minutes for their SLOW system to eventually find the package I needed I was told that I would have to pay a Migration fee as I was too early renewing (my contract expires 27.08.2022) ....??? All I'm TRYING to do is to renew my contract WITHOUT having to buy a new device. I am extremely happy with my Samsung Galaxy S10 and don't see why I should get another device. I was also told that my new contract was too "big" -what does that even mean? The lady helping me did not exactly give me reassurance on her knowledge of packages and possibilities available to me. I believe all these obstacles are merely to force me to upgrade to a new device- Is this what MTN classifies as customer service?