It is the duty of the shipping FFL to report a theft or loss in transit.
You have 48 hours from discovery to report the theft or loss
First, contact the carrier to determine if they have any information or the firearm. Determine what they are doing to locate the shipment and tell them that you will report the loss to ATF after 48 hours has elapsed.
If they have no information, call your local law enforcement agency to report the theft or loss. Contacting the local law enforcement authorities is essential to the quick recovery of firearms taken in a crime.
Second, call the ATF’s Stolen Firearms Program Manager toll free at 1-888-930-9275. They can also assist in the preparation of the Theft / Loss Report for submission. ATF will work with the local law enforcement authorities investigating the theft.
Third, You must report this to the appropriate local authorities. If the location of the theft or loss is known, the local law enforcement agency at that location would be the appropriate local authority. Otherwise, the report should be made to the local law enforcement authorities at the licensee’s location or business premises.
Fourth, complete the report form (ATF Form 3310.11) and email or fax it to ATF’s National Tracing Center. Be sure to submit the original form(s) to ATF and retain copies for your records and proof that you sent the form. This form is used for losses on premises and in transit by licensees. Provide the appropriate local authorities a copy of the report.
note: You can create this form in FastBound after you’ve started a Theft/Loss Disposition.
Last, after making your report to the ATF, you must update your A&D records
In FastBound you will need to Undispose the item(s).
Then you will need to dispose the item(s) as a Theft/Loss.