What manufacturer does your Safari use for the jacks?
If you only have 3 Jacks - Two in the back and 1 in the front - then it probably is RVA
On my coach, the tank / pump unit is in the right rear adjacent to the Engine. Follow the hydraulic lines to one of two manifold assemblies - The one with 3 more hoses going from three single solenoids is for the 3 Chassis Jacks - The one with a single hose going from two solenoids is for the Slide Out - You may have an additional double solenoid / single hose setup if you have two Slides
On the top of the three solenoid / three hose block there are three T-Handles - one for each Chassis Jack. If you open them, it will allow the hydraulic fluid to run from the Jack back into the reservoir allowing the Jacks to retract -- If this works, then one of the solenoids is sticking and will need further attention
If your system is an RVA, the factory helped me in the past with a couple of items / has spare parts / etc.... Even had a nice conversation with Dennis Kaye - Owner / Original designer of their Jacking System - (760)746-5732 -- Very Friendly / Customer Oriented
Hope this helps with your situation