Question why the error ip configuration not valid pops up?

[technologicalpixel]

basically all my pc connected with ethernet to the modem, sometime work and sometime don't, when they don't i get the error "ip configuration not valid"

This is happening from when i changed my modem/internet connection , probably is configured bad but i have no idea of how to check it

This problem pops up only on pc connected with ethernet, all wifi device are connected and have no problem

also if i change the spot of the ethernet cable multiple times then it work again, or if i do right click on the internet icon in the bottom right of windows and then "troubleshooting"

Does anyone know why is happening and how i can fix it? thanks!

 

[Ralston18]

Try another known working Ethernet cable.

The current cable may be defective in some manner. Sometimes works, sometimes does not work.

What make and model modem, router, or modem/router if combined?

 

[technologicalpixel]

the model is TIM ,

anyway i tried multiple cable but i'm sure the cable are working fine because with the old modem everything works fine