Xiaomi India - Security app issue

I am using Kaspersky antivirus for my PC and with its good performance I bought Kaspersky internet security for Android and after * or * months the security app has changed my default antivirus to other antivirus provided by the company itself. And I tried to change it a bit it wasn't allowing me to change it. I contacted both Kaspersky and Xiaomi customer support so I came to know that the problems were from Xiaomi security app and the customer people told me to raise a feedback issue from the security app and I did the same but till now there isn't any reply from them. And the Kaspersky antivirus which I got it for money I have it for useless. And I bought it for real-time browsing security against online fraud but now lying waste in my phone. So kindly resolve the issue by providing the default third-party antivirus option ASAP. Now I have only *** days of the subscription.