Once an auto-attendant has been activated, whether or not a phone number has been assigned yet, it can no longer be edited. This is because the Auto-Attendant route builder saves changes in real-time, and we don't want you to accidentally break an active call flow, even temporarily. 

If you just want to see how the auto-attendant is set up, click   to open it in View Only mode. But if you do need to make changes, you have two options:

Option 1: Duplicate, Edit, Switch

1. In the Voice Portal, navigate to Business Cloud > Auto-Attendant to access your auto-attendants. Locate the one you want to modify, hover over it, and click   Duplicate.
2. Click   Edit to open the builder and make any necessary changes.
3. Return to the Auto-Attendant page, find the one you just modified, and click Activate.
4. When ready for the new version to go live, click Assign Phone Number to move to the Phone Numbers page and locate the phone number assigned to the original auto-attendant. Adjust the destination on the right to the new auto-attendant.
5. Click Save. Calls to that phone number will now be directed through the new auto-attendant.
6. Go to the Auto-Attendant page, locate the original, and click Deactivate.
7. Delete the old version or rename it, so users don't confuse them.

Option 2: Deactivate, Edit, Reactivate

Important Note: This option should only be used after hours to ensure that no calls are received while you’re making the changes.

1. In the Voice Portal, Business Cloud > Phone Numbers from the navigation on the left. Locate the phone number assigned to the auto-attendant you want to modify.
2. Click the phone number destination on the right and change it to "None" or another viable option (like a temporary auto-attendant).
3. Go to the Auto-Attendant page and locate the one you want to modify. On the right, click
   Deactivate.
4. Now click   Edit to open the builder and make any necessary changes.
5. When you're done, go back to the Auto-Attendant page, locate the auto-attendant you just modified, and click   Activate.
6. Click the Assign Phone Number link to go to the Phone Numbers page.
7. Locate the phone number you want to assign, then click the destination on the right and change it back to the auto-attendant.
8. Calls to that phone number will now be directed through the auto-attendant.