Unable to obtain an access token for scope: /spec/lti-ags/scope/score

Hello,

We are encountering an issue with our LTI 1.3 Moodle integration related to score submission.

While logging in and accessing the course works seamlessly, we are unable to send back the score. The error message we receive is as follows:

"Unable to obtain an access token for scope: /spec/lti-ags/scope/score"

Upon thorough code debugging, we identified that the retrieval of an access token (/mod/lti/token.php) for the specified scope is resulting in a 400 Bad Request. The scope causing this problem is:

"spec/lti-ags/scope/score"

We would greatly appreciate any assistance in identifying the cause of this issue, or any guidance that could point us in the right direction.

Technical Stack:

• Laravel 10
• LTI-PHP (v5.0.0-rc1) (celtic-project)
• Moodle 3.11

Thank you for your attention and support!