Your lines include a block of phone numbers. Under Einstellungen (Settings) and Durchwahlen (Direct numbers), you see how many are assigned, available, and in total.

1. Open Einstellungen and Durchwahlen.
2. Select Durchwahl zuordnen (Assign direct number).
3. Under Freie Durchwahl (Available direct number), select a number.
4. Under Klingelt künftig bei (Rings at), select the destination: an extension, a ring group, a queue, an auto attendant, or voicemail.
5. Select Vorschau (Preview) and Übernehmen (Apply). The number now rings at the destination around the clock.
6. Optionally, you then set another destination outside business hours with Nachts woanders (Elsewhere at night).
7. Call the number from outside.

You can also select Aktionen (Actions) and Durchwahl zuweisen (Assign direct number) directly on an extension. Confirm there with Zuweisen (Assign).

On a direct number, select Als Hauptnummer (As main number). With Automatik (Automatic), you clear the setting again. For the main number, build the call flow.

1. On the direct number, select Freigeben (Release).
2. Enter the phone number to confirm.

The assignment is then in Trash and can be restored there.

Under Einstellungen and Leitungen (Lines), you see your lines with the displayed phone number, direct numbers, and simultaneous calls. The view is read-only. INGOS sets up new phone numbers and lines.