Wireless Disconnection on OpenWrt 21.02.1 with D-Link DSL-2740B rev F1 (bcm63xx/AW4339U)

Dears I have flashed OpenWRT 21.02.1 on D-Link DSL-2740B rev F1; currently I have setup the device as wifi extender following the OpenWRT guide.

After the disconnection from the device after one hour the wifi has been automatic disabled.

Here some screens captured after a login via ethernet cable:

https://drive.google.com/file/d/1Lkq_KA7VGtYK3x4dNFHRSSX40cWfHg-J/view?usp=sharing

https://drive.google.com/file/d/1QLZT-Gt6DdaHRTMHBVvQUIwwvl_2IIxL/view?usp=sharing

https://drive.google.com/file/d/1bIk3eHLqb4K2Y6q24kWFe0FvvuYGs0lh/view?usp=sharing

In the screens you can see: "Error: Network device is not present", any suggestion to solve the problem?

Thanks in advance
K

See if this thread helps?
https://forum.openwrt.org/t/wifi-ar922x-not-detected-after-upgrade-18-06/18338/23

Sound strange because wifi is working fine till I'm using it.

I'm using wifi since this morning and all is fine, but one hour after the disconnection the wifi doesn't work any more.

Could be some energy saving settings?

Perhaps you have found a bug in 21.02?

The link I provided predates release of 21.02.0.

Test an older version of OpenWrt given your rev.F model has been supported since 2014 ?

Yes could be a bug, but I can't install a previous version cause I'm using the device for my daily work.

Could I support the project debugging a little bit more?

The dsl-2740b is a single band wireless router. You're not using ADSL port?

fwiw, could the issue also be caused by using the single wifi radio for both functions as a wireless client and as an Access Point?

Are there any error messages in the system log?

Wait and see if any other reader can offer any suggestions.