@DigitalVirtual 

Hi,

I don't know what would fix the problem, but if your TL-WR841HP is indeed a "V5" with firmware version 0.9.1 2.0 from April 2018, then you might want to consider updating it to the latest available firmware version.

The crucial thing for selecting the proper firmware for any TP-Link router is that the model description printed on the label on the underside of the router matches the description of the firmware update package. (i.e. if the router model is "TL-WR841HP(UN)_V5" then the firmware update must also be named "TL-WR841HP(UN)_V5")

In case the content of your country's TP-Link website is not being updated regularly, then you may also check for newer firmware versions on other TP-Link websites, for example the "Global /English" (Worldwide / English) TP-Link website.

  @woozle Thanks for your reply. The firmware of my TP-Link TL-WR841HP router is on latest version, and matching the hardware version written on the sticker. Still the problem is the same; however it works on 54Mbps.

  @DigitalVirtual 

Ok. So your are probably on firmware version 0.9.1 2.3 Build 220922 now, but no improvment.

I don't know what else to do. Actually, this could also be a limitation of the other wireless router to which the TL-WR841HP connects to.