@Alessandro_ya, I ran out of ideas and am afraid that I cannot help you any further remotely like this.
Please, pack your MAKERbuino unit and send it back to us:
Maksimilijana Vrhovca 11,
I will personally take a look at your device, fix it and return it to your address as soon as possible.
Send the package as a registered tracked letter, it shouldn’t cost you more than 9€.
Thank you for your patience and understanding, please PM me the tracking number once you ship or contact us directly via email@example.com