Error with Time Tracking Report

When following the exact instructions in this link: https://docs.gitlab.com/ee/user/project/time_tracking.html#view-a-time-tracking-report

after clicking on the ‘Time Tracking Report’ link on the right sidebar of an issue (for which I have logged several timestamps, the cumulative value of which is correctly being presented above the ‘time tracking report’ link), I receive a blank report (i.e no rows; adding up to 0 hours) and a ‘Something went wrong. Please try again.’ error on top of the page.