I am also a developer.And i can say there is no meaning in saying "Provablity fair is making me loose".
Provability fair is a system that proves the user site is fair.Before every game site gives you a hashed string(Or other variations of the main hash,it depends on the system)after the bet it gives you another string,it is the unhashed string if you hash that string with the correct algorithm it gives you the first string so it proves site is fair beacuse it actually gives you the bet result but you cant understand it cause it is hashed.

Sooo why i am loosing eventually?
Well it is the simple math lets say you have %50 chance to win the bet if you are wrong you will loose your money.But if you correct you will double it but you if you won't cashout the money your chance will drop to %25 in other bet.So you will eventually loose.the important thing is you should know where to stop,have a nice day.