TP-Link Archer C50 won't connect to the internet

[Deleted member 2621623]

So, today I got my ADSL modem exchanged and after the installation my TP Link router stopped recognizing the internet coming from the new one.
It's not the cable, because I can connect anything to it and I have access to the internet. It's not the new modem either, because my PC is right now directly connected to it via the same cable I was trying to use on the TP Link router, which was working fine till today.
I really think it's something related to the router or the modem, but I'm not really sure and I couldn't find anything online.
Also, the WAN light on the router stays orange/red and blinking slowly, like it's trying to connect but it can't. I don't know what it might be. On the IP address of the router it says the WAN port is unplugged and on the IP address of the modem no LAN connection appears when connected to the router via ethernet cable, but my PC shows up. Maybe the port is damaged somehow or they're not compatible? It's good to know that the new modem is VDSL, which I don't really know what means.
Please help.

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Router model: TP-Link Archer C50
Modem model: Mitrastar DSL-2401HNA-T1CC

 

[jsmithepa]

I suspect your new modem is a GATEWAY, an all-in-one box with NAT function built-in, you would know this if there are 4 LAN ports on its back. If this is the case, you should configure the tp-link as an Access Point, don't use tp-link WAN/Internet port, there is a STICKY by the Wireless forum if u want explanation and step-by-step.

 

[Deleted member 2621623]

I suspect your new modem is a GATEWAY, an all-in-one box with NAT function built-in, you would know this if there are 4 LAN ports on its back. If this is the case, you should configure the tp-link as an Access Point, don't use tp-link WAN/Internet port, there is a STICKY by the Wireless forum if u want explanation and step-by-step.

I don't understand much of this subject, but, yes, there are just 4 LAN ports on its back. And I shouldn't use the WAN port? I'll try to do this. But will I still be able to use the LAN ports of the tplink router?

Thank you for your help. Hope this works.

 

[Deleted member 2621623]

Nothing I tried worked.
Somehow there was some sort of issue with the cable (?), I don't know why. I bought a new cable yesterday and everything started to work just fine as before.