Meeting times not populating

I am trying to set up a schedule with 30-minute meetings, and then have 15-minute breaks built in. For example, 3 30-minute meetings from 6:00 AM - 7:30 AM, a 15-minute break, and two more 30-minute meetings from 7:45 AM - 8:45 AM. The first three meetings show up on the schedule, but then the next meeting begins at 8:00 AM, and only gives me four 30-minute meetings instead of five. I tried changing the Time Increments under Availability Options to 29 minutes per another thread, and that does give me the 7:45 time, but the second meeting starts at 6:29 AM, the third meeting starts at 6:58 AM, and so on. Any ideas? Thanks.