By following query, I found the problem was "EFW.CONNECTION.CONNECT=Off"
pi@raspberrypi:~ $ indi_getprop
EFW.CONNECTION.CONNECT=Off
EFW.CONNECTION.DISCONNECT=On
EFW.DRIVER_INFO.DRIVER_NAME=ASI Wheel
EFW.DRIVER_INFO.DRIVER_EXEC=indi_asi_wheel
EFW.DRIVER_INFO.DRIVER_VERSION=0.5
EFW.DRIVER_INFO.DRIVER_INTERFACE=16
EFW.DEBUG.ENABLE=Off
EFW.DEBUG.DISABLE=On
EFW.SIMULATION.ENABLE=Off
EFW.SIMULATION.DISABLE=On
EFW.CONFIG_PROCESS.CONFIG_LOAD=Off
EFW.CONFIG_PROCESS.CONFIG_SAVE=Off
EFW.CONFIG_PROCESS.CONFIG_DEFAULT=Off

Then I set as;
pi@raspberrypi:~ $ indi_setprop "EFW.CONNECTION.CONNECT=On"
I got the control of EFW, and my Bash script did worked. Thank you all.
BTW, please let me know how to set "EFW.CONNECTION.CONNECT=On" automatically, or permanently.

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