[amsat-bb] AO-07 Popularity?

I’ve put out calls a number of times on AO-07 as it passes over Australia and while I hear my own single back clearly I’ve never had a reply. I guess I’m curious if there is a calling protocol I’m missing, or a particular part of the passband etc? As a higher altitude bird with great coverage it would seems logical to me that it would be popular? Am I missing something?

James.