sony xperia m4 isn't recognized by pc

hello,

I have a sony xpera m4 aqua, tonight i was deleting images and it suddenly got in a boot loop

within a hour i connected it to my pc to resolve the problem with the xperia companion app

everything was going all right but in the mid of the repair i got an error code UEU.... and the repair stopped.

so i tried to turn my phone on but now it is completely death, the only thing that works is a blue led.

if i put it in my pc via usb. my pc gives an error it cant recognize.. my phone shows up as ''unknown device''

androxy's sony mobile flasher doesnt recognize it and xperia companion too..

Does anyone know how to fix this?

greets from holland