Cannot enter fastboot mode topic

So, recently my mum's Neo L had issues with the digitizer so I went ahead and ordered a new one online to replace it for her, after the replacement, the phone does not boot and has the led blinking red if I plug it to the wall, plugging it into my pc makes the "usb device not recognized" message pop up, tried entering fastboot mode to flash with flashtool by holding down search and plugging in the usb cable and its the same story, ideas?

Thanks :D