I can only get true pleasure from sex in certain positions

Hello friends,

This is sort of an embarrassing subject, but thankfully the anonimity of this forum sure helps a lot.

So here goes: bit of a back story. I used to be very introvert and never had friends until I entered college when I was 20.

My first time having sex was when I was 22 and then I had to make up for lost time.

So I dated and had sex with many girls until (when I was 27) I met a girl that became my girlfriend for 6years.
It all went well but as she was afraid of getting pregnant, even though we had "conventional" sex she would 90% of the time finish me off orally. And I believe that I got too used to that!

Eventually life happened and that relationship ended. I went on to have fun for 3-4years and then, some months ago, I met a new girl I really love.

So here's the problem. We have great sex, really great sex, but whenever I'm on top I can never really get absolute pleasure from those positions.
In short, I'm not able to cum whenever I'm in missionary or doggy etc.

However I'm able to orgasm whenever she's on top. Any position.

I believe this is from my "troubled past"... too many years masturbating (14-22) until being able to meet girls and then getting bad habits from that 6year relationship.

How do I solve this issue? How can I get absolute pleasure from positions where I'm on top?

Thank you