Here's the update. MSM fixed the problem. They reported the A/C gas was less than normal. Now the cooling is perfect. However, I have kept it under observation just in case it drops again due to some leakage.
From the day of buying, I am having another issue. Not sure if this is an issue. Check with another Ritz(P) owner and he does not have this however it's a manual transmission.
Upon cold start, the rpm shoots up to 1500 and settle to 900-1000. During this time, a grinding noise is heard and engine noise is annoying.
Is it a AT car feature? DZire or Astarte AT owners also throw some light.
Please help me if this is some issue with the car.
Recorded a video of the issue.