[rootlinux]

So the dialer works unless you end a call that has yet to connect and is still dialing?
Does the hard end key work?

Maybe the delay for the dialer needs to be changed.
Try this. Go into the Advanced Config app in the tweaks folder.
Scroll down to phone options.
Check the End call delay.
It should be set to 0.
If it is then try setting it from 1 - 3 and see if that changes anything.

Just something to try and not sure if it will help or not.