How do I remove an administrator?
 

My husband and I very recently divorced, about a week ago. When I first got my forum he, being move web savvy than me, created two administrators of the forum - himself as #1 and me as #2. Considering the circumstances now, I do not want him to have administrative capability of my forum. I’m not sure where or how to remove/change this and because he created himself as #1, if it is possible or will cause issues. Does anyone have a suggestion on where to start? Any help is really appreciated.