Defensive & Arrogant Manager at Telkom

I recently went to the Telkom store at the Pavilion in Westville to buy a phone. I did tell the salesperson that I am used to a Samsung & a Huawei phone with an android operating system. The salesperson sold me a Huawei phone and did not inform me that the phone had a Huawei operating system. I am a senior citizen and was unable to use the Huawei operating system. 2 days later I went back to the store to change it for a phone with an android operating and informed the manager of the store of my problem and in the future, the sales persons must inform clients about the Huawei operating system. The manager of the store spoke to me in the presence of other clients and was extremely defensive and arrogant. They did not swap my phone. Currently, I am battling to use the operating system and I have a 2 year contract.