A supervisor in an educational institution has the following responsibility:

He has to send reminders to the department heads, faculty and coordinators for 3 different reports that need to be submitted by them on a daily (1 report) and weekly (2 reports) basis, to the supervisor. This is the institution's policy and the Academic Heads' instructions.

But the thing is the dept. heads, faculty etc, have a lot of other work to do, and as such either forget or do not pay importance to sending the reports in.

Now the supervisor has to either call them up, or send them emails or move around the entire building to locate them in person and verbally ask them to send the reports in, which have their own drawbacks. Emails can be easily ignored, and a call/verbal reminder can be forgotten in the next second, especially when you have so much in your mind.

So the question is: In what way can the supervisor remind these people to submit these reports, in a way which do not irritate them, and get the work done? Better if the supervisor does not have to remind them at all, because rules are rules, and they have to abide by them, and they are not kids that they need to be constantly reminded.