@Taky34 

Surprised to see the same error on a new router. What model did you purchase?

I have a AC3150 that I purchased in 2018 and have seen the same problem several times. Something to do with voltage and grounding. 

https://community.tp-link.com/en/home/forum/topic/159271?replyId=560694

If you can return the TP-Link and get a refund then I'd say it's the best option.

I pulled out a old LINKSYS router and getting more juice out of it's 5Ghz (300 Mbps) and almost threw away the TP-Link Router since I only got 173 Mbps on it's 2.4 Ghz band.

I'm not getting 5Ghz at all to turn ON and that's when I see the error.

TP-Link Support couldn't solve the problem I was noticing and after several emails they told me I was out of the 2-year limited warranty and offered a 10 - to 15 % on their refurbished routers :-) . Newer ones with Wifi 6 are cheaper at walmart or Amazon hahahaha

If you are under warranty try to contact TP-Link support and get a replacement (new item, not rejumblished :-)

Good Luck