My HWH jacks have a pivoting mount that allows about an inch of side to side movement at the ground contact plate. If that's what you have I'd consider that normal.
Do you have the owners manual for your leveler system?
Manuals are a free download from HWH web site, and have a troubleshooting section.
Welcome to HWH Corporation
Have you checked the fluid level in the reservoir , with all the jacks retracted?
If your only having the problem with the one jack , and trying to cycle it, leads to hydraulic lock , and the pump stopping , I'd say the jack needs replacing .