Help - Zoho CRM and Forms integration

Help - Zoho CRM and Forms integration

Hello,

I hope someone can help me with this one...

After converting a Lead into a Contact, I would like to send him/her an email template with a link/QR code to a Form with:
  1. Pre-populated basic fields that come from the Lead profile
  2. Many other fields to be filled by the person in order to update their Contact profile in the CRM
I followed the steps from Zoho instructions, red many other threats here in the community and still couldn't make it work.
When I click in the link from the email template, I can access the form, however, the basic fields are not pre-filled, I can't search anything at Zoho's CRM advanced field and, after submitting the form, the Contact profile is not filled with the data. 

Thank you in advance for the help!