John Deere x738 mower stopped working suddenly

My JD X738 only has 33 hours on it. I was mowing the other day just fine & suddenly the mower part quit & the steering became difficult and stiff. I drove it into the garage to check it out. Hydraulic fluid, Engine Oil, & Coolant levels were all normal. I then restarted the engine with no problem, however the mower won’t engage, i can’t raise the mower the the hydraulic lever, and i can not move the machine forward or backwards. The only things that work are the engine , instument panel, and headlights. The problem seems to be hydraulic in nature. Dealer says they are running 3-4 weeks behind.