keyboard not detected.(usb hub + OTG)

[John Titor1]

Hello guys..

I have a 7 ports usb hub.
It has a power input but not sure what type ..

I wanted to connect a mouse and keyboard to my Android device at the same time using a hub and otg.

The mouse worked perfectly.
But the keyboard wasn't detected via the hub(no power in the keyboard).
But, for a couple of seconds .. The numLock blinked and the keyboard was detected and went off again.

Using hub + OTG
Everything
(mouse, flash driver.. Etc)
work fine except keyboard

Using otg directly
Everything works fine including the keyboard.

The product on amazon :
https://www.amazon.com/Generic-7-Po...ag=hawk-future-20&ascsubtag=UUacUvbUpU6213147