Web Interface not working- dump1090-Mutability

I was able to get my dump1090 working with the lighttp web server, but I get the following error:
Problem fetching data from dump1090.
AJAX call failed (error: Not Found). Maybe dump1090 is no longer running?
The displayed map data will be out of date.

What would be the cause of such an issue? Is there something I can do to fix this? Thanks!

Did you install via the Debian package? If not have you set up --write-json

I installed following this link here:Flight Radar
It looks like the debian package.

I dont know if this helps, but the flag that I have set is:


--aggressive --interactive --net --net-http-port 8080 --net-sbs-port 30003 

Perhaps I need to set a different port?