I'm going to keep this short because it doesn't normally need an arguement:
If you have the /setwarp ability, you should most definitely be able to delete your own warps without requiring staff assistance...
You should be able to use /delwarp on your own warps. The Essentials plugin should allow this as well as any decent warping plugin so the fact that a staffmember specifically ordered this to be a rule (or an incredibly strange warp plugin) is quite unusual...
If you have the /setwarp ability, you should most definitely be able to delete your own warps without requiring staff assistance...
You should be able to use /delwarp on your own warps. The Essentials plugin should allow this as well as any decent warping plugin so the fact that a staffmember specifically ordered this to be a rule (or an incredibly strange warp plugin) is quite unusual...