Big thanks to all the suggestions for getting barn doors unstuck , none really help much once you put drawers in and a cargo barrier and shelving so ended up removing small door glass and destroying door card and fixtures that were inthe way .
After a crap load of stuffing around I pulled the grommet for the demister and managed to get a tent peg down to trip the stuck latch, then removed locking system soaked and rushed in diesel and all good again.
My advice to anyone with rear drawers if you haven't done it remove and clean lock mechanism, there was no warning with it always very easy to open but the Great central road has done a bit of grief to this and campereven thoughroad wasmostly ingood nic.