I visited honda gateway in Lahore and only inquired about cat cleaning, they said sorry we don't do this.
Seriously...
I'll visit some other S3 dealer and then get my car checkup. I'm now facing power loss as well and fuel average is going down too.
Checked NGK spark plugs they are available in Rs 8400 for 4. So I'll buy them and try to check their resistance reading to be around 5k (if they got meter and allow me to test).