Hi @robinson-pete56,
Thanks for your post and welcome to our Community Forums.
I'm sorry to hear you're receiving a "Line Cord Error" on your handsets. I've ran some checks on my end, and everything is showing to be within acceptable parameters and are green across the board.
Your Hub has been online for an extended period of time, can you please perform a full reboot (turn it off using the switch on the back and waiting for 10-15 seconds before turning back on), so we can run some further tests? Can you please confirm how many handsets you have connected?
Cheers,