HELPP! Missed university fee deadline, should I pay now or wait till Monday?

My fee submission deadline was 28 August, but my dad forgot to submit it because we were busy with a family function. I just realized it this morning (29 August, around 8 AM). Today is Saturday and the university is closed on Saturday/Sunday, so I’m not sure what to do.

Should I submit the fee right now after the deadline has passed, or should I wait until Monday and contact the university first? I’m worried that paying it now might not be accepted, but I also don’t want to lose my admission by waiting until Monday.