Hi Abbey,
I hate to report that we've been having this issue on and off for years now, without much 'support' success between our LMS provider and articulate support. Articulate support will tell you to ensure you've tested using SCORM cloud.
A useful suggestion i've had in the past was to ensure the following settings in the scormdriver file:
var EXIT_SUSPEND_IF_COMPLETED=true;
var EXIT_NORMAL_IF_PASSED=false;
To do this - you have to:
1. Export the package from articulate as normal
2. Select the SCORM file and 'extract all'
3. Open the scormdriver.js file
4. Find the settings mentioned above and check they are set correctly. If not correct, change them, re-save the file. If correct, exit, proceed to step 5
5. Re-zip (compress) the SCORM file
6. Import to LMS