"Selected to ADIF" - missing entries

[ND2K]

I highlighted my January log entries, right-clicked & chose "Selected to ADIF".

As a sanity check (I'm a new user), I looked at the ADIF file that was created and there are entries (QSO's) missing.
I did this 3 times with the same result; what would cause this? I see nothing unique about the omitted QSO's; for instance
some 40m FT8 QSO's are present while others are not.

Thanks....Al ND2K

[G4POP]

Did you try filtering what to export in ask manager and export to adif from there and have the same result?