How do I regain access if there is no recovery partition?

I have an android tablet which has no recovery partition, as I have been told in the place where I bought it.

When I hold the buttons for the recovery mode, the image of the robot with the front open up shows, but no menu is shown. There are no vol+ nor vol- buttons but I attached an USB keyboard and hit arrow-up and arrow-down keys with no success. The keyboard is correctly detected, I have use it with this tablet.

I forgot the password and cannot log in. The device is not set in developer mode neither.

Is there any workaround for this or will I have to throw the tablet in the bin?