HTTP2 is available but server refuses to use it why it may be?
I found solution over Internet and I am updating this to help people who encounter the same problem. when I examined the apache errorlog file, I found a warning that goes like...
[http2:warn] [pid 8494] AH10034: The mpm module (prefork.c) is not supported by mod_http2. The mpm determines how things are processed in your server. HTTP/2 has more demands in this regard and the currently selected mpm will just not do. This is an advisory warning. Your server will continue to work, but the HTTP/2 protocol will be inactive.Then After an hour of googling, I came to know that this is an issue with the prefork module while configuring HTTP2.0 on apache. You can find more on this particular issue and a detailed steps to configure http2 at this location..
If you don't want to have any troubles while configuring http2 I hope this document will help you for sure.
I followed those steps and my problem was solved.