Try entering time values by hand in the time field and note any differences between what you enter by hand that does not trigger an error and the values entered from the value list.
I was able to set up a custom value list on a time field with values 1:00pm 2:00am 3:00pm and had no trouble selecting one to enter a value. In your example, I see "p.m." instead of "pm". That might explain why your value list didn't work as that will trigger an error due to the periods whether you enter the value by hand or select it from a value list.
That works. Thanks. (It was the periods causing trouble)