Date-Time fields Not Updating Time

Date-Time fields Not Updating Time

Hello,

I have been having an issue for months with date-time fields. I need to update the times on a lot of them for events/meetings, but it only gives me 1:00 am or 1:00 pm as options in the drop down. I try typing directly into the field, but it will not let me. I edit the entire potential and try to fix it there, and it still won't work.

How can this be fixed?

Thanks,
Hannah