hi, My Archer C60 router is working very good. it gets the internet from fiber cable. the problem is that there is a certain PC that cannot connect to the internet. even though i have connected multiple phones and a laptop to the wifi in same time without any issues. now, i need to solve the problem of this PC which is every time it connect to the wifi , the router redirect the PC to the page of  " The WAN port is unplugged" alarm. and in same time all other devices working properly.