Deleting and completely erasing an Ipad before returning it to work

I am searching for some information on how to permanently wipe a work Ipad as I have moved on from that job and need to return the ipad. I have tried the regular method of Setting-Gen-Reset and Erase all, however, the Erase all portion is no longer there. I only have the Reset option, which doesn't delete any of my information. Any help would be greatly appreciated.

Also, I should mention that the ipad is controlled and managed by the company, so perhaps they have blocked me from being able to do so?

It is an Ipad mini 3