VMU suddenly stopped working

[soniccd123]

Hello, would like to ask if someone has had the same problem as me.

My Dreamcast VMU simply stopped being recognized by the system. I had been playing with my system for a month now, before it was stored in my closed for like two years. Till today everything was fine. The really strange thing is that the VMU still shows the images from the games at its screen normally, it just is not recognized by the system. I tried tearing it apart looking for bad components or solder joints and found nothing, also cleaned the contacts without success. I also tried the same VMU on other controller and the controllers on other ports but none worked. At the system menu the VMU keeps the exclamation icon on but it is not recognized.

Thanks,

Soniccd123

PS: Tried to put some CR2032 on the VMU and start it by itself, it turns on normally but when entering the file viewer mode, it gives System Error 40.