Konsole launches and runs fine.
If I run any program in konsole (run in terminal), like ranger, it gives the error,

could not find the program 'Konsole'

I use shortcut to launch ranger and every time I trigger it, I get the error.
Launching ranger inside konsole works fine, i.e giving the command

ranger

in Konsole starts ranger without any problem.

This issue was reported around may 11th and right now, it's status is "RESOLVED FIXED"
[bug] https://bugs.kde.org/show_bug.cgi?id=421374 [/bug]
I updated my KDE Neon to the latest build, 5.19.0, and i am still experiencing this bug and don't know what to do to fix it.

Latest update seems to fixed the problem.