@Kevin_Z Hello, thanks a lot for the explanation. Does it mean that my router is using its non-original firmware? Because the back label shows the harware version is DE... If so, I'm going to ask for...

@Kevin_Z Thank you for the reply. The firmware version is as same as the above mentioned one: 0.6.0 1.1 v007a.0 Build 170112 Rel.65475n The hardware version on configuration website of the router is...

@joleo Hello, same problem as mine. Have you found any solutions?