My HTC dersire 816g won't turn on anymore

A

AC Question

Whilst my phone's android software was updating, ignorantly i had to remove it from the AC adapter to go do something and the phone went shut-down, since then it has been inoperable even though i've tried doing everything possible ; deleting all my files and datas and trying to install a new software amidst an SD card but still all to no avail.
Please what do i do at this moment to bring back the phone to normal, i need your help.....