Cannot delete or edit inventory template..

Cannot delete or edit inventory template..

I'm trying to re-edit a quote 'inventory template' and the edit buttone is greyed out, when i hover over it, i get a pop up that says
'Sorry, You cannot edit of deletethis template as it has been deployed through the plug in'
i have no idea what the 'plug in' refers too and need to be able to edit this, can anyone tell me how to do this?
ive had no issues editing this prior to today.