Unfortunately, there is not a way to identify spoofed numbers because they come along the same path and look the same as a legitimate phone call. You or your customer can report these calls to the FCC fur further investigation. Below are some helpful links on Spoofing:
https://www.fcc.gov/consumers/guides/spoofing-and-caller-id
https://consumercomplaints.fcc.gov/hc/en-us/requests/new?ticket_form_id=39744
https://opendata.fcc.gov/Consumer/CGB-Consumer-Complaints-Data/3xyp-aqkj