Problem submitting the SalesIQ WordPress link

We are unable to save the SalesIQ WordPress link in the WordPress plugin. We created the link following this process:

https://help.zoho.com/portal/en/kb/salesiq-2-0/installation-guides/articles/wordpressinsalesiq#Getting_your_Zoho_SalesIQ_WordPress_link

Then when we try to add it to the WordPress plugin the following error appears:

Forbidden
You don’t have permission to access this resource.

Then the website stops working and a Captcha appear instead of the homepage. After a minute or so, everything is back to normal but the SalesIQ WordPress link is not saved.

The page I need help with: [log in to see the link]