Triggering a custom event loop after API call

I’d like to be able to remind my users after every 3 days of being sent a message. For example, if I send a message, I set a variable on their account as action_needed = Yes. This should trigger an event that cancels all previous scheduled workflows and now waits the 3 days from the time it was triggered. Once they do some action, I’d set their action_needed = No and then cancel all scheduled reminders for that particular user.

It would be nice to have some sort of 3 stage process where I’d mention that it’s the first email, then if they don’t reply, I send another second email saying that “this is our second attempt”, and then finally “this is our final notice”.

I’ve tried creating a Trigger when action_needed = Yes, it should activate and send me a test message. For some reason, it never gets triggered once I schedule an API workflow that would set the user’s variable = yes.