There currently exists an html form on my company's website that allows a user to enter their email address and select one or more checkboxes to subscribe to our newsletters (in other words, it adds their email to our corresponding contact lists for those newsletters). As it stands, the form properly adds new emails to the first two newsletters, but not the third. Here is a link to the page: http://newyorkfamily.com/newsletter-sign-up/
The reason it does not work properly with the third is because we only recently moved that newsletter over to Constant Contact from another email marketing client we were previously using. We have migrated our old list of contacts into a new one within Constant Contact, and we would like to mimic the process that the first two checkboxes carry out in order to successfully add new emails to that newly created contact list.
Because this functionality was put in place before I started working at this company, I am not familiar with the methodology used to accomplish the end result of adding new users through that form. In my brief attempts to follow the trail of this data along its path to Constant Contact, it appears that the form data is sent within a JSON object through a function defined within the file "nyf.esub.js" - I have not been able to determine the point at which the data really is sent to Constant Contact, however, as it seems this JS file merely prepares the form data within an object to be sent.
You may notice within the HTML code on the web page itself, something along the lines of "wpcf7-"... This is simply a form-generating plugin that allows HTML forms to be created more easily using shortcodes rather than typing out all the HTML from scratch - it also sends emails to a predetermined address any time the form is completed successfully. However, I do not suspect this plugin has anything to do with the data being sent to Constant Contact.
I managed to find another thread (linked to below) that tries to achieve the same result but using different methods. Perhaps it will be of some use in addressing this issue here.
If the current process that sends the form data to constant contact cannot be replicated and applied to the third checkbox/newsletter list, then I would be open to exploring alternative methods that accomplish the same results.
Thanks for your consideration of this issue.