Hello Declan,
Happy to help!
We recommend testing how your course behaves in a different LMS such as SCORM Cloud to verify if the issue you're experiencing is isolated to your LMS. Here's a helpful guide on how you can test your courses in SCORM Cloud.
If the behavior is specific to your LMS, please work with your LMS provider so they can fix the issue on their end. If you are able to replicate the behavior in SCORM Cloud, would you be willing to share a copy of your project file here or in private by opening a support case so we can take a closer look at what's happening? We'll delete it when we're done testing!