Manager Created Assignments BY PERSON not consistently working - help

Summary:

We receive tickets DAILY about a manager having trouble assigning a learning item to an employee. I ask them for a screenshot of the assignment form prior to them selecting submit, and everything is filled out correctly. They submit, the processes run and succeed, but the learning doesn't appear for the learner. The issue seems to occur mostly when the manager is assigning by person rather than direct reports (though we have seen tickets around this, too).

Content (please ensure you mask any confidential information):

I've been working with my IT team since early August, and we've had an SR open since then, too but Oracle is providing zero recommendations or solutions to this problem. This is a HUGE issue for us because we push the field to do their own assignments on annual training vs it being done by an admin.