Battery

It will be replaced for free if it drops below 80% within the first year. 92% is pretty normal for a 1 year old phone, there is nothing wrong with your battery, you can expect on average a 1% drop per month with normal usage.

It will be replaced free of cost only when it reaches below 80%

In your first post you said your 1 year warranty is almost up, indicating you have been using it for almost a year. Then you said the percentage is at 92%, that does not equate dropping 3-4% a month. Even if it's at 90% that is pretty normal, a 10% drop within 12 months is perfectly fine.