@rsantacruz 

Hello, have you tried with different Ethernet cables between your modem and the C1200 WAN? Ensure your modem LAN port is still functioning, then try with different Ethernet cables and see if the Internet LED on the C1200 will turn on.

Just a quick test maybe, you can connect the WAN/Internet port to your computer and see if that Internet LED will light up, maybe in orange.

If none of these makes it light up, the WAN port might be faulty, you may confirm with the local tech support if this is covered by the warranty, thanks:

https://www.tp-link.com/en/support/contact-technical-support/#Hotline-Support

@Kevin_Z 

Thank you very much for your answer. Tried doing everything you mention and the issue was not resolved. I have already contacted the TP Link customer service line in Colombia, I must send the equipment for review, most likely the WAN port has been damaged as you mentioned.

@rsantacruz 

Thank you for replying, please keep in touch with the local support, I think they will help you resolve this, good day.