First check this please: How To Format Messages in This Discussion Forum - #2 by abcd567
Post the configuration again, formatted properly.
Also get the complete configuration i would assume some is cut off due to the editor.
cat /etc/default/dump1090-fa
Then check the log for dump1090-fa, maybe you find the issue yourself.
--net-only --device-index 0 --gain -10
Just as a first hint, this doesn’t make sense does it?
Check
dump1090-fa --help
See what each option does and how it doesn’t make sense.