We have been successfully using a custom Drupal 7 based LMS for last 4+ years in order to store activities sent from our e-learning modules using TINCAN API.
We have been having issues whereby HTML5 version of e-learning modules are no longer to interpret responses from our TINCAN API activity states endpoint. Thus always taking users to Slide 1 when e-learning modules are revisited. Problem happens in modules built using Storyline versions 3.2.x and 360. No issues when Flash version is displayed in the LMS.
Any input will be greatly appreciates. Attached HTTP request and response headers.