my daughter scare of the male teacher?

xother

currently my daughter (4.5yr old) is learning swimming with a class of 3 kids and all of them are about 4-5yrs.
First few lessons was fine and she was very excited at the beginning. After Easter holiday, she told me she doesnt want to swim with boys and I have tried in the last 3 weeks, she refused to even jump inside the swimming pool and crying for 20mins by hanging on the side! Last week was worse, the other girl also affected by her by not wanting to go for the same teacher!
She was perfectly fine with water and she is willing to join other class with a female teacher, but just not that male one. I cannot switch her to other class as it is a higher level.

Just wonder if anyone has similar situation ?