"I don’t understand those…"

This just happened

Me: so just to confirm. The spelling of your surname is S for Sierra, M for Mike, I for Indigo, T for Tango and H for hotel?

Customer: oh why do you have to speak like that. I dont understand those. It’s S for Sugar, M for Mother, I for India, T for Tommy and H for Harry.

Yeah ok. So i spelt it right then