Disco II sitting squint at the front

Wonder if anyone can help me here/

My 2001 Discovery II is sitting slightly higher at the NSF than OSF. I haven't made any tyre, suspension, ANY changes recently.

can anyone suggest what might be making either my nearside front lower or the offside front lower? As I'm unsure which one has the problem.

if fitted with gas shocks osf shocker poor but mostly osf front spring

Thanks James for your quick reply.

I also notice there is more wear on the NSF tyre's outer edge so was wondering if the 2 things might be related?