I received an error "199 CALL CBP FOR EXPLANATION". What does it mean?

I received an error "199 CALL CBP FOR EXPLANATION". What does it mean?

If AMS Air users encounter this error please send the eManifest again as an "add" or FRI. 

This is a known CBP issue. 

If sending again does not work, please look over your submission file if it contains any special characters.  Remove the special characters and send the file to CBP again.