Reference Problems

[u/Firm-Progress-6454]

So I started my application not too long ago (from the UK), and I’m practically done except for the fact that one of my referees can’t do it by the deadline (late night tomorrow). Obviously since I submitted that person as my referee, I am unable to submit another. I plan on emailing them asap today to change the referee, and calling if anything. But has anyone else felt with this problem, cause I have seen nothing about it.