I have the same problem as you.
What I do to release the pressure is attemp to hook up one of the QD's first. If it goes on, great...if not, I touch the valve handle to pressurize the other QD. Then the one I'm trying to put on has depressurized. You will have to see which way to bump the valve handle for each QD on your machine. Then I bump the valve handle the other way and it pressurizes the QD I just put on and depressurizes the other and I can push it in and lock it.
One other thing I noticed.
Sometimes the diameter of the male QD gets a little banged up. I run a file or some wet and dry sand paper over the male ends to get rid of any burrs or dings. They are fairly close fits. This does not hurt the seal since the seal is an "O" ring of some sort and not the OD of the male QD. It also does not hurt the spring loaded ball retaining method, since those balls ride in the groove on the OD of the male QD. I found doing this lets then enter and exit easier.