This does not work for me:
CIN-SL-5506# show reload
Reload scheduled for 03:00:00 IST Wed Jan 9 2019 (in 15 hours and 26 minutes) by admin from ssh (remote 192.168.10.159)
CIN-SL-5506#
CIN-SL-5506# show module sfr
Mod Card Type Model Serial No.
---- -------------------------------------------- ------------------ -----------
sfr FirePOWER Services Software Module ASA5506 JADxxxxxxxx
Mod MAC Address Range Hw Version Fw Version Sw Version
---- --------------------------------- ------------ ------------ ---------------
sfr 4001.xxxx.xxxx to 4001.xxxx.xxxx N/A N/A 6.2.3.8-51
Mod SSM Application Name Status SSM Application Version
---- ------------------------------ ---------------- --------------------------
sfr ASA FirePOWER Up 6.2.3.8-51
Mod Status Data Plane Status Compatibility
---- ------------------ --------------------- -------------
sfr Up Down
Can you give more info or context as to the specific steps you took, the appliance model etc? May be I am not doing something exactly like you did?