Apple India — No proper warranty claim from apple

I have purchased iphone XR 128 gb. In the June 6th and from day 1 I had mic issue only on voice call. Issue type is in ongoing call after 2 min the other end people can feel that voice keeps decreasing slowly and goes totally off and again after 30 sec voice start increase... Due to lockdown I took the mobile to plant care located in Indiranagar and they took Device and they sent it to apple and after 7days I received a replacement device... Where again the issue was repeating... Again the Device has submitted ... So nearly 10 days gone I don't have any backup device also ... I was struggling a lot on behalf of your service as well the quality ... All my family members use to buy apple products because of their quality and reliability but here fishy... Please give a best solution now atleast