Default need help, brick my phone after flash a kernel desire 816n a5ul

hello my name is Giorgio, and I have a problem, I have my phone (Desire 816N single sim eu a5ul) flashed with grakernel. now I have a bootloop at the htc white screen.

I have tried many things, flash ruu, flash custom rom, flash with sideload, flash 3 different recoveries etc. nothing helps...
recovery says cant mount data or cant mount internal SD...
Flash with sideload say cant write data...

please help