t595 loosing and regaining hydraulic function

Hello, I have a 2016 t595 that I purchased to use around the farm. It was recently serviced by bobcat and has been running great. A few days ago, I topped off the hydraulic oil, just under the red line. I went to use it today, engine starts just fine, I press the green button, turn the throttle up and when I start to go I slowly loose all hydraulic function. It seems to be building too much pressure and not allowing the hydraulics to function. Once this happened I checked the hydraulic level and it was above the red line. I drained fluid out to get it below the red line and the problem persists. Thank you in advance for any help that keeps me from calling bobcat out. Have a good day!!