How to completely clear phone, (root, info, accounts, etc.)?

My Meizu M2 note think it is rooted but it isn’t, all my apps doesn’t know there is even root. I used rootchecker and a bunch of other things, but none, except for the account page, says there is root. So the most logical route (for me) is to clear it all out, start as if it just came out of the box, is it possible?
A little backstory:
i rooted the phone before, but i factory reset it for some reason and now i don’t have real root permissions (even if it looks like it), but the phone claims it has root, Can’t unroot, can’t root, running the latest flyme software. I tried to update firmware but it just says it is corrupted every time. i tried to factory reset, but it doesn’t actually clean out everything. Busybox doesn’t work either. How can i reset everything (root, files, everything)?

Contributor

@99problems F.a.q. read it all!

To un-root your phone you have to update + clear data, is the best wasy to have a pretty clean new system.

It’s also not possible to put an “I” firmware on a Chinese phones.

last edited by Ultrametric

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