Have you gone through this?
https://community.librenms.org/t/new-requirements-for-1-40/4057
Maybe you could try to add /debug=yes/
at the end of your URI and see if it shows up some errors
Have you gone through this?
https://community.librenms.org/t/new-requirements-for-1-40/4057
Maybe you could try to add /debug=yes/
at the end of your URI and see if it shows up some errors