Out of stock so why waste my time

Cell C called me because one of my contracts was due for upgrade. They persisted to call and when I answered, I explained that I did not know that the contract was due for upgrade and would need time to think about it. The agent who was very friendly, asked if he could call me later to which I said ok. While driving home he tried to call many times and I finally answered. I upgraded over the phone with him and got confirmation that it is completed. Today someone calls me to say that the phone is out of stock and is now trying to get me to change the phone I told that person that if they don't have the Samsung J4 plus that we agreed on then please cancel the order. She persisted to tell me about an Huawei phone and I explained that the phone is not for me but for my mother. She then said she will e-mail me...still waiting I am saying this again. Cancel the order because if you call me and don't check if there is stock, then why waste my time. I don't want any other phone but what we agreed on. The phone is not for me but for my mother so I don't want to change it from Samsung to Huawei like they are now trying to sell me