Unable to login using my Apple ID to download software from App Store

After my WiFi card stopped working (which I have not fixed yet) I am not using Ethernet adapter to browse the internet.

I tried to download updates to my MacBook Air from App Store but when asked to login using my Apple ID I get the next error message:

"Your device or computer could not be verified. Contact support for assistance."

I have not been able to even download new software, my computer is becoming obsolete just because it is not able to communicate to Apple Servers. Is it possible that my Mac addressed has been banned from the server? I already changed my ID but have the same problem.