Cant root my Samsung Galaxy tab A again I rooted my phone with king root. Everything was working perfectly,  until one day I felt like I should make my phone new so I went to factory to reset the phone, at that time I didn't know anything about root, but I rooted it because I used it to play games to get good graphics.
After reseting it stucked at boot. Then I sent it to a shop for repair, the repairer told me he had to upgrade to higher android before it will work. It was 5.0.1 then he upgraded it to 6.0.1 but now I want to root my tablet again and it won't root. Have tried like 50 times using kingroot and kinggo root but it won't root.
Please I need help
Kingo root??? not a good try you can use pc and there are so many other tools that can surely root any android

either way you can flash twrp or cwm recovery with adb
adb command you can use:-

"fastboot flash recovery path-to-the-recovery-file"

and then by using twrp or cwm you can flash SuperSU.zip