Block or restore class access for unpaid tuition

When an installment is still unpaid after the payment deadline (5 business days after the due date — the day the final notice says class access is restricted), the student shows in Accounts → "Block class access" and their page shows an amber "Past the payment deadline" box. Click "Block class access" and give a reason: Cohort records the block and suspends the student's Moodle account, so they can't open their classes; their student portal tells them access is paused and points them to Payments. Once they have paid, Accounts shows "Restore class access" against them; open the student and click "Restore class access" to re-activate Moodle. For the Moodle side to work, the Moodle web service used by Cohort must include core_user_update_users; if it can't reach Moodle, the page says so and the account must be suspended or re-activated in Moodle by hand. Every block and restore is kept in the history.