I think there is problem with DL award ticket system. I want use DL mile for a CZ award ticket on Sep 30. But DL agent told me that there was no award seat available that day for the flight I requested.

I checked with CZ and learned that there was two seats available on that flight. In order to make sure it is not the CZ's problem( I orginally thought that maybe CZ did not release the seat to skyteam member airlines), I checked with KE and KE can see the award seat.

Anyone has such experience? Is Delta deliberately masking the award seat? How to fix this problem?