If you have an OTG Internet source, you can attach it then fill the form and request a new PIN on your email address. You can then use the PIN to unlock the tablet or perform a factory reset. To do this simply, look for something sharp and press the reset button located on the margins of the tablet. It should be a small hole where you can push a button. Press the button for a few seconds while the tablet is connected and the reset process will begin or turn off the tablet and then press Volume Up + Power Button until the Android logo appears. Select Wipe Data / Factory reset and wait for the operation to complete.
You might need to configure the tablet again once the operation is finished.