I have to different types of forms, ninja forms and getsitecontrol and both have undefined classes. I have set up tracking i google tag manager, with tags, triggers and variables, but in the piwik pro debugger, all the trigger trackable events are undefined.
Hi there!
Could you share the URL of the website you’re reffering to? You can send it to me via private message or here in the thread 
Can you explain your issue a bit more? I tested the forms on your website and both of them send a valid custom event that shows up in the tracker debugger.
When i try to set a trigger in piwik tag manager, i select form submission, and then choose “when all conditions are met” - from here i cant track anything. i’ve tried setting the from id as the action, but to no avail. I cant seem to get the custom event to be tracked? The tag is not fired in the debugger
In the debug mode, the formID is undefined, so is the form url, form path and all of the drop down options in the form submission in tag manager trigger.
How can i track the forms?
I think i figured it out - After setting the event as a data layer event, the conversions and tag is now triggering.