How can I set an out of office message for a shared mailbox?

In an internet browser, modify and enter this URL in the address bar:
- https://outlook.office.com/mail/*@stalbans.anglican.org/
  - * = insert the shared mailbox alias (first part of the address) here
- Alternatively go to your mailbox in Outlook on the Web
  - Click your name in the top right
  - Open another mailbox
  - Enter the email address of the shared mailbox
  - Select address
  - Open
In the shared mailbox go to Settings (cog icon) top right
View all Outlook settings
Automatic replies
Turn on to enable or turn off to disable
When enabling select the time period
Write your message for inside and, optionally, outside your organisation
Save