I accidentally addressed a male admissions officer as "Ms." -HELP PLEASE

There was an admissions officer who emailed me to remind me of documents that my guidance counselor had not yet submitted. Thinking it was very urgent, I replied as soon as I had read the message.

After the officer replied, I suddenly thought about how I addressed the officer. Then I researched the first name (it was in an unfamiliar language) AND FOUND OUT THAT HE WAS A GUY.

I AM SO MORTIFIED.

I was thinking of apologizing along the lines of: “Also, I’m really sorry with how I addressed you earlier. It won’t happen again. I was so mortified when I realized what I had done.”

How should I apologize? Please reply asap

Do not mention it, this is a trivial matter.

Take a breather. No big deal.

Wow there will be more “mortifying” things in the future.

This won’t matter, at all.