It depends on your schedule settings, but likely the Reading you are wanting to do is for next weeks meeting? Which is in 2019, so it is not in the 2018 schedule.
Actually, there could be a bug in my code related to this being the last week of the month. I will look further but I think it will resolve itself over the next week. Sorry for the hassle.
The funny thing is that the Weekly Reading Schedule for 2018 is working fine on my iPad, but not my iPhone. Wierd.