How can I delete root access at Meizu m2 note?

I have Meizu m2 note, firmware. Root permission has received in the fourth (on which fourth I forgot) firmware. I updated over the air from fourth ver. to But root stopped working. SU file in the system/xbin is standing but I can not remove because it needs root permission but I do not have it. Please tell me how can I solve this problem? I do not know what to do me.
P.S (Sorry for my English. I have bad grammar)
P.P.S (I am from Ukraine. If someone knows russian write me an email or 0_1482596814878_root1eng.png ) 1_1482596814878_root2eng.png 2_1482596814879_root3eng.png

Meizu m3s

Lots of people gets errors when updating firmwares. Have you clear userdata when or after updating? What happens when you use terminal(app) and type “su”? Have you tried to use King root to fix root (usually fix or give error).

Looks like your connection to Meizufans was lost, please wait while we try to reconnect.