@Joseph-TP thank you very much!

>Therefore, its 2.4 GHz band indeed does not yet support 802.11ax. so is this a matter of hardware/chipset or software/firmware ? you posted a screenshot before this post where you showed this option...

here you see the model name and firmware version

unfortunately, there is no such uption in my router Firmware Version 1.2.12 Build 20260327 rel.40355(4555) Hardware Version TL-WR1502X v1.0

Hello, i have a bunch of rather exotic Mercusys MA14N AX300 Nano Wireless USB Adapters , which do support AX mode, but only can do 2,4Ghz. currently they won't connect any faster then 54Mbs with...

problem has been resolved by tp-link support with latest beta firmware 1.2.12 Build 20260327 rel.40355(4555)