Error code: invalidsesskey
* line 494 of /lib/setuplib.php: moodle_exception thrown
* line 85 of /lib/sessionlib.php: call to print_error()
* line 216 of /lib/externallib.php: call to require_sesskey()
* line 59 of /lib/ajax/service.php: call to external_api::call_external_function()