I see no issues from the device side.
ARP table of the router shows valid entries of the connected devices, IP addresses appear to be leased properly, no disconnections. Also, wireless clients connect at 17:05:57 and 17:11:47, meaning that the access point itself is visible and discoverable for other devices for more than 30 seconds.
The logs show Windows and MacBook clients. Do both of them experience this issue? Have you tried an Android smartphone?
Also, what does exactly happen? Do devices loose internet connection? Are they not able to ping RUT240? Do they lose DHCP settings? Does the router become unresponsive?
If you configure a static IP on your computer (instructions for windows) with RUT240 LAN IP address, are you able to access the router?
Could you update router's firmware to the latest (download link) with Keep settings option disabled and see, if the behavior persists?
Another device reset option you could try is via bootloader menu, as instructed here. Though, as mentioned, the issue does not seem to be the router.
Best regards,