Triggering multiple times timer boundary event on a user task

Hi all,

I have a user task where the user can stay up to 7 days. I want to notify the user (push, email, sms) after 1, 3 and 6 days, always at the same time. How should I configure a Timer Boundary Event (non-interrupting)? I’ve started with setting Duration something like (for minutes, not days) “PT1M,PT2M,PT3M” but I got a parsing error.

Any ideas?