Interactive Video and Activity Completion Issue within Moodle

Hi, we have experienced issues with activity completion and students getting stuck when using the Interactive Video H5P activity on moodle. 

We use iomad on moodle version 4.1 on our elearning platform. We initially had this same issue a few years ago (2019/2020) with moodle 3.8 when we first tested it, but decided to change completion settings on our H5P activities to complete on viewing, as many users were initially having a lot of problems.

Users were complaining that they were completing the interaction within the video, but not seeing a submit screen. When clicking on the star icon at the end of the video, they just saw that no completion had been submitted, but there was no option to submit. This was not happening to all users however, the majority were getting through the course without issue. 

We were able to recreate this issue last year, by navigating out of the chapter after completing the interaction and before submission, and then going back into the chapter. But when we tried this again after updating the H5P plugin in around March of this year, we could not see any issue. 

And so, thinking that the issue had been fixed by an H5P upgrade, we updated one of existing course's activity completion settings to require a grade before completion could be marked on that chapter, and released this to our clients. Users have continued to have issues with this course after this update and are getting "stuck" in their courses, unable to complete every chapter. And we are also now unable to recreate this issue.   

We would ideally want every user to have to complete the interaction and submit their response in every chapter in order to mark it complete, but are unable to do this, as users keep getting stuck when this setting is switched on.   

This has happened to users in multiple browsers (chrome, firefox, edge, internet explorer etc..).  

Any help on this would be appreciated.