“Next” link at bottom of series list is not functioning correctly

When we have a sermon series with more than 10 sermons there is a Next link at the bottom of the list of sermons.
When I click on Next it takes me to something other than a listing of the next sermons in the series.

i.e. Our Acts series.
https://calvarychapelrosarito.info/en/sermon-hechos/
When I click Next it takes me to the Romans sermons in lieu of the next Acts sermons.