TP-Link M5 Mesh: one point not seeing it is connected with cable

[DeonH]

Good day and thank you for your help.
I installed a Deco M5 AC1300 (3-pack) two days ago.

Main: Living room and is connected to the router into which our fiber plugs in. This is a TP-Link TL-WR845N. The Deco Main in connected to this router with the flat LAN cable that was in the box.

You will notice on the second picture below that there is an orange exclamation mark with the following message: "Abnormal WAN port speed. Please check your WAN port connection"
Question: What does this mean exactly and how do I solve it? Is the supplied cable wrong? I know I must check the port, which I have done. I have even tried other ports. Please advise on how to optimize this.

Study: On the second picture you will see it shows that this point it connected to main (living room) with Wi-Fi. Problem: this is not true since it is connected with a cable. Question: How do I fix this that the point in the Study "knows" that it is connected with a cable and not Wi-Fi. You will see that the 3rd point, Main Bedroom, is connected with a cable plugged into the Study point (1st picture).

Please advise on how to fix this.

Thank you for your help.

 

[Anthro]

Deco M5 is capable of Gigabit (1000Mbps)
TP-Link TL-WR845N is only capable of Megabit (100Mbps)
Reconfigure the Deco M5 to become your primary router and send that shitty router back to where it came from

 

[r00igev@@r]

Deco M5 is capable of Gigabit (1000Mbps)
TP-Link TL-WR845N is only capable of Megabit (100Mbps)
Reconfigure the Deco M5 to become your primary router and send that shitty router back to where it came from

My hammer is available to do the job! Professionally deinstalled....

 

[Anthro]

My hammer is available to do the job! Professionally deinstalled....

@DeonH send your address, we have a hammer for you

 

[DeonH]

Thanks for the reply. I eventually learned that the M5 has DHCP. This is the only reason I kept the old router. All sorted now and running smotth.