Zoho User created own instance of zoho CRM

Zoho User created own instance of zoho CRM

So I have a user that has access to Zoho Connect and Zoho Recruit, I sent her an invitation for Zoho CRM. Instead of using the invitation link she navigated to Zoho CRM and created her own instance of Zoho CRM. 

  1. How can I as a company administrator prevent this from happening?
  2. How can I close that CRM instance and give her access to the company version I set up?