issues with running the l2switch example program

[elizabeth-hi-cell]

Hi
I am trying to run the commands in their order in https://github.com/p4lang/p4pi/wiki/Example-%231---Simple-L2-switch-(default-program)
and I have met this error

Launching P4Runtime-shell...
CRITICAL:root:StreamChannel error, closing stream
CRITICAL:root:P4Runtime RPC error (UNAVAILABLE): failed to connect to all addresses
CRITICAL:root:Failed to establish session with server

I am using raspberry pi 4 and connect to it via ssh session.
I would love some help
thank you.