As tech who spent years working on CNC, industrial machines and robotics, with high pressure hydraulic systems
You have a restriction problem somewhere in the system
Or the hydraulic pressure regulator ( if one exists in your system ) is malfunctioning
When pumps fail they loose pressure, unless there is an internal regulator that is failing
Machine systems all had external regulators attached to the output of the pump, which then feed the manifolds containing the valves
So those are the two choices, restriction
Or
Failing regulator ... internal or external
