Unable to Assign Salesforce Task to a Queue When Using the Activity Timeline in Lightning Experience

When the Record Page Settings for a record type are configured to use the Activity Timeline, the Task creation form launched from that timeline uses a simplified action that does not expose the Queue option in the Assigned To field. This behavior is working as designed in Salesforce Lightning Experience.

To confirm the current Record Page Setting, administrators can go to Setup | User Interface | Record Page Settings and check whether it is set to Related List or Activity Timeline.

Workaround 1: Change Record Page Settings from Activity Timeline to Related List

1. Go to Setup | User Interface | Record Page Settings.
2. Change the setting from Activity Timeline to Related List.
3. Create Tasks from the Open Activities related list — Queue assignment will now be available in the Assigned To field.

Workaround 2: Keep Activity Timeline and Add Open Activities Related List via Lightning App Builder

Administrators who prefer to retain the Activity Timeline view can use Lightning App Builder to add a separate related list component:

1. Navigate to the record page you want to edit (for example, the Account record page).
2. Open the page in Lightning App Builder: go to Setup | User Interface | Lightning App Builder, then select the relevant page, or use the Edit Page action from the record.
3. Add a Related List (Single) component to the page layout.
4. Configure it to display the Open Activities related list.
5. Save and activate the page.
6. Users can now create Tasks from the Open Activities related list on the same page, and Queue assignment will be available.

Note: Components cannot be added directly to a page layout. This must be done by editing the Record Page in Lightning App Builder.