Tailgate Adjustment?

I noticed today (well, the guy at the garage actually) that my tailgate isn't straight and seems to lean to one side a little. It's the whole boot not being straight, there's not damage or anything like that.

Is it possible to move it to straighten it up at all? If so, how?

 :dontknow: Cheers for any input.

Adjustment is possible at the hinges under the headlining.

Thanks dubboy, much appreciated.