Time setting on iPad

Hi,

I’m trying to schedule meetings on my iPad, but it onlyseems to allow very quarter hour for the time setting. I need to schedule for 10:40, 11:50 etc, but it won’t let me. I’ve tried tapping the time, but nothing comes up to allow me to change the time to anything other than the quarter hour slots. It’s easy to do on a laptop though. 
How do you do it on an IPad/iPhone .

thank you