[Unanswered]  Second hand Beylogger Plus linked

Hi,

I bought a second hand Beylogger Plus so both my kid and I can have one, but when I got it the Beylogger was aleady linked to another account. I can access that account, so I looked for the mail of the account linked and wrote an e-mail to the previous owner but he never answered. 

So I was wondering if there's any way I can unlink the account it have linked without knowing the password of that account. I tried pressing the reset button but doesn't seem to do anything and the delete account option on the app is asking for the password of the previous owner.

I thought I might reset the chip somehow, but I only have basic notions on electronics and have been unable to do it by myself. 

I'm out of ideas, so if someone can help me out I will be really grateful.

Thanks!