Convergence issue

[sandy]

Dear sir
I'm running a simulation of Black Phosphor Tunneling FET, but after many time-consuming iterations, the convergence is not obtained and the result has a fluctuating behavior.
I use a computer with CPU: Cori7, 3.6GHz  RAM:24 GByte
The script has been attached.
Any help will be appreciated.

[Umberto Martinez]

It would be interesting to see the log file.
do you have problem for your zero or finite bias calculations?
You can try to increase the k-point sampling along the C direction to something like 200 points.