You will need to be an organizer of the event or have Full Write Events to perform this action. This also only applies to events that are configured to need rooms and resources.
One-Time Events
Navigate to the event that contains the resource request you want to edit. Go to the "Resources" tab. All the requests for that day will appear. Note that you can click on a room or item to view additional details such as setup notes and custom question responses.
A pop-up will appear where you can edit the details of the request.
Repeating Events
There are multiple ways to edit an individual resource request for a repeating event.
The first way is to go to a specific day on the repeating event. This is the same as the steps in the section named "One Time Events" above.
The second way is from the listing of all requests for the repeating event. Navigate to the event and go to the "Resources" tab. Then click on the "Manage All Requests" button. A pop-up will appear containing requests for all days in the repeating event. Search for the one you want to edit and click on the "View" button at the end of the row. This will open a pop-up where you can edit the details of that day's request.
If you do not see the request in the table, make sure you select the right view (i.e. Past or Future) depending on whether the day the request has already passed or not.
Keep in mind that editing only one request will not prompt the update of the series since approval may be required.
In this situation, the most effective option would be to delete the resource requests for the recurring event (which can be done in bulk) and then submit a new request that includes the missing resource.
Helpful Tips
If you edit a room or item already there that requires approval and was previously approved, it will go back to pending status. An approver will need to review the request again.