Why do I get duplicate WOs for an asset w/an activity with the same due dates using Maint WorkBench

Oracle EBS 12.2.10 Enterprise Asset Management application (EAM)

We have a few PMs that for some reason generate multiple work orders for the same activity and due date when using the Maintenance Workbench (MWB). For example I have an activity A1234 assigned to asset E7890 which is to be performed every 90 days. When I run the MWB for the period where the PM will come due, I get four separate entries (work orders) all due the same day for Asset E7890 with Activity A1234. If I forecast out for a year, every 90 days, instead of getting a single work order with this asset/activity combination, I get