I have become a regular member of a group I used to be the owner

[AHD]

I shared the group with another person sometime ago, and he (or probably me) decided the other person should do the moderation, and thus gave that person all control. I later found out that I became a regular member and I have no control on the group. 

Now, I can only see the email. The group has been inactive for some time, but I want to reinstate it. Is there a way to be the owner again?

Thank you.