Need to empty a Zoho CRM field when a contact is updated using the API

When updating a Contact record using the Zoho APIs, a field that has data needs to be cleared if there is not data for that field when the record is updated via that API.

I've tried this with both Gravity forms and Zapier.

Here’s the scenario and example:

We need contacts to verify or correct the mailing address we have on file (in the CRM) for them.

The address fields consist of:

%Street Address 1%
%Street Address 2%
%City%
%State%
%Zip%

An example initial address, that is automatically populated in a Gravity form is:

Street address 1: 123 Main St
Street address 2: Suite 200
City: Portland
State: Oregon
Zip: 97210

In the Gravity form the contact corrects the address to this:

Street address 1: 456 First St
Street address 2:
City: Portland
State: Oregon
Zip: 97210

The %Street Address 2% field needs to be empty in Zoho CRM. But after the record is updated, the “Street Address 2” field in CRM still contains “Suite 200”.

This seems to be a Zoho API issue. I’ve come across this in other CRM systems and understand the logic, but it is a problem for this use case.

Any ideas on how to make this use case work?