DT71 won't turn on or charge

yorit

When I try to charge the device with the USB C connector it does give a red led indicator. It will never turn off, even letting it charge for a couple of hours.
When connecting the display unit while charging it gives this screen:

DFU:V3.52
5.230V

but when I disconnect and connect the display to the tweezers it does absolutely nothing.

I tried to upgrade to the latest firmware DT71APP106.hex but when I try, the hex file is replaced with the file attached.