I cannot see calls in Calls by Source

Make sure that there are no "Destinations not assigned to Destination Groups".

You can find such Destinations in SETTINGS -> Setup -> Integrity Check and assign Destination in several ways:

• Add Destinations to Destinations Group
• Reassign Destinations to Destinations Group
• Destinations not assigned to Destination Groups

Destinations which are not assigned to Destination Groups will be not shown in Calls by Source.