How can i fix my minidigger [1.5 tonne JCB Mini-Digger]?

I have a 1.5 tonne JCB mini-digger manufactured around 2002 which i am having problems with; the tracking, sideways movement and bucket movement have all stopped. The engine works fine but there is no hydraulic drive whatsoever. The selaniod valve is working correctly in conjunction with the safety levers (i am aware of only one valve on this machine) and the hydraulic fluid level is correct. This digger stopped working abruptly with no warning.

I wold really appreciate any help with this issue if anyone has any insight into what may be the problem.

Many Thanks
Trevor