my pc wont recognize sm-n920p

as the title says
i cant load it,it has frp lock and i wanted to remove it with my octoplus box but my pc wont recognize it,already downloaded the files from the samsung official page,but it aint working,shows it as unknown device .
any idea ??also download mode aint working when plugged to my pc wont set it as a com
it is updated to the latest samsung ota update aok3 or something like that.
but the problem is that my pc aint detecting it