Removing AM/PM from a timestamp since the user "should know that already"

I am not a native english speaker, so therefore I reach out to you with this question.

We have a case where a user "does something" in our application at a given time. The next day, the user will come back to the application and we will present this timestamp to our user.

We are discussing wether we should include the "AM/PM" indicator for this particular timestamp or not.

What would be the best approach here? Mostly reaching out to native English speakers.