Step Function not waiting to the specified time

Hello everyone,

I face a rare case in my process where some step functions are not executing well. We have thousand of step functions executed per day, they all start with a wait state until a specified timestamp (timestampPath). Usually the waiting state is from 1 to 6 minutes. But sometimes it waits for multiple hours before to resume the rest of the process without any error.

I have already checked that I did not send a wrong timestampPath

I have no clue on what can provoke that.

thank you for your help