Error You have an error in your SQL syntax; check

When I click on the Process button for a new subscription, I get the following error.

"Error
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 4"

How do I fix this?

Hi Franklin

Look like there is something with data on your site (as mentioned on your other forum post)

Please submit a support ticket sending us super admin account of your site and the link to subscription form. We are going to check to see what's wrong and get it sorted for you

Regards,

Tuan