Not letting me edit posted Volunteer Opportunities

Edit Subject

Every time I try to edit a volunteer opportunity (add a pic or edit the text) it takes me to the user log in page. I sign back in to prove to the request that I am the manager of the content but the same thing will happen again. It allows me to only change active or inactive expiration dates...can't seem to edit anything else.
I waited passed the weekend thinking it was maybe just a website error but the problem is still here.

Thanks for taking a look at this.
Organization: Tamarack Nature Center