How to build deb "dbg" packages?

Hello, I use "make-debs.sh" script to build debian packages, but instead of getting *-dbg packages, I get packages like "ceph-base-dbgsym_14.2.7-75-g14b67dbc11-1_amd64.ddeb", which cannot be imported by reprepro, with errors like: Unknown file type: 'a2e592c703334bc9f55a62f6fac267d8 135503940 debug optional ceph-base-dbgsym_14.2.7-75-g14b67dbc11-1_amd64.ddeb', assuming source format... Warning: File 'ceph-base-dbgsym_14.2.7-75-g14b67dbc11-1_amd64.ddeb' looks like source but does not start with 'ceph_'! I must have missed something about the package building procedure. What supposed to be the right way to build deb packages? Best, Can Zhang