Error

hi good after noon.
i m getting the following fault messages on my display screen

connection disconnected: steuerung _1, Station 2, Rack 0, slot
Value could not be written to the PLC, when we try to put some instructions

please help us out
Thanks
Houyhnhnmss

I'm sorry my crystal ball is broken.

If you want help you need to provide a lot more information,
such as
the brand of HMI and PLC, what method are the 2 devices connected by,
ethernet ?, serial ?.