Error: Email can't be sent using this from address --- zoho.loginuserid

I have a custom button that calls a function which sends an email using an email template.

The button works as intended, but only with the from address zoho.adminuserid. I want this email to come from the user pressing the button, but when I set the from address to zoho.loginuserid, I get this error:

{"data":[{"code":"INVALID_DATA","details":{"api_name":"email","json_path":"$.data[0].from.email"},"message":"Email can't be sent using this from address.Kindly check the allowed from address list","status":"error"}]}

This page says that zoho.loginuserid is a valid from address. https://www.zoho.com/deluge/help/misc-statements/send-mail.html.

You can specify the system variable zoho.loginuserid as long as the user is not a customer portal user. If the user is a portal user, the email address has to be verified before it can be used as the FROM address.

Since the button/function/email template are working and the zoho.loginuserid is a valid address, why am I getting an error?

emailTemplateId = 2050955000064358113;

from_name = "Test User";

from_email = zoho.loginuserid;

to_email = "testemailaddress@gmail.com";

email_subject = null; //the subject gets overwritten by email template subject

template_data = {"id":emailTemplateId};

emailData = {"data":{{"from":{"user_name":from_name,"email":from_email},"to":{{"email":to_email}},"subject":email_subject,"mail_format":"html","template":template_data}}};

sendEmailResp = invokeurl

[

url :"https://www.zohoapis.com/crm/v2.1/" + module_name + "/" + record_id + "/actions/send_mail"

type :POST

parameters:emailData.toString()

connection:"send_crm_email_template"

];