I added the mail application to my ZohoOne and now i cannot add anymore mail users. 

I had to deactivate ​8 users​ for which i used when free and had an email account/address before this​

 What is this? I could have 25 users on the Free plan and now i pay for each email i want under ZohoOne?

I thought ZohoOne offered the same email features as Enterprise?  It does not!