Installation and server related problems

I have installed H5P (current version) in Moodle Moodle 2.6.11.

The installation was carried out without problems, but when inserting an H5P activity and trying to access it from the course, the browser shows the following message: HTTP 500 error.

We have tried modifying the read and write permissions of the hvp folder and moodle data folders and still showing the same error.

We have tested with browsers: Chrome, Firefox and Edge.

Please, could you help us solve this situation?

Thank you.

I get an "invalid security token" when trying to install any content type

We have created an H5P course and loaded it into learndash via the H5P button (shortcode) and when you access the course you get the error message every time you click on a slide. It runs fine when testing the content in the plug in area. What can cause this?