Am receiving an error message when trying to add accounts

Am receiving an error message when trying to add accounts

We recently resurrected our free zoho CRM tool. I am able to delete an edit accounts, so I deleted about 15 accounts and merged about 20+. When I went to enter some one new account, I received an error:

"sorry you have reached the maximum limit in your current edition" 

I received the same error just trying to add a contact, etc. Any ideas?