@aykuttasdelen Yep - it's very disappointing. Just return it. It's not fit for purpose.

a Sunshine wrote @au-user Hi, thank you very much for posting on TP-Link Community. 1. Please connect a computer to the router via Ethernet cable to see if the speed is normal and stable, if not,...

This is for the AX80 model with the internal antennas. https://www.tp-link.com/au/home-networking/wifi-router/archer-ax80/ I can't get this router to maintain throughput on 5Ghz 802.11ax 80MHz...