Can't create campaign because of email address is in use error. Please HELP!

Can't create campaign because of email address is in use error. Please HELP!

My co-founder, Kushal ( kushal@customerguru.in) keeps getting an error whenever he tries to create a campaign from his login. Please see attachments for the error and the campaign settings of the only campaign I have active from my login. Please help us resolve this. 

Thanks,
Vivek