Translation help please

Could someone help me please?
How do I say

Please pay (your ogessha) by March 22nd, 17:00.


I have a student who has been taking my lessons but hasn't paid me for over 2 months.
How can I be polite but firm about this?

Many thanks in advance ...

You're going to say it, right?

- Gessha desu ga, san-gatsu niju-ni-nichi no yuugata go-ji made ni, haratte itadakemasu ka? (As for your lesson fees, could I get paid by March 22, 17:00?)

Or maybe (I don't know how your lesson bookings work but) you could tell the student that she/he can book the next lesson only after they've paid the tuition so far, or something like that? Let me know if you need more suggestions.

Thank you very much AK.
I will try the new phrase !
I really appreciate your help .