Sorry, i was disconnected.
So, i don't remember clearly but there simply was a button in one of the TWRP's tools.
It was written on it: format /data (or something like that).

I don't know if i am in the right category but i don't know where to put it.
Actually, i have a meizu pro 5 on the last ota of ubuntu os before they stop supporting it.
And i changed the passcode to an 8 caracters one using the passwd command (in the terminal emulator) . But the phone take only 4 caracters when unlocking.
So, i was unable to unlock it any more.
There, i tried to hard reset it with the recovery mode. But it didn't work, so thinking that it will clear the users
data i used the fastboot -w command (in the fastboot mode of course).
And now, when i try to boot it, the meizu logo just appear than stay a few seconds and disepair. Befor starting again the same way and it continue like this booting and exiting.
So have you any ideas of what is going on and what to do to make it work again (on ubport of other)?
Sorry for the anglish quality.

Sorry, i was disconnected.
So, i don't remember clearly but there simply was a button in one of the TWRP's tools.
It was written on it: format /data (or something like that).

Very well, the /data partition was corrupt.
I have just formated it with TWRP and restored the backup.
The phone work very well and i directly made the update to ubport version 2.
Thank you very much for the help and the files.

Actually, i tryed to reboot it using TWRP.
And now, it continually boot, enter TWRP, and reboot immediately, i have no time to use TWRP meanwhile.

I can't access TWRP, it is booting in cyrcle.
So maybe i should reflash TWRP.

I tried to reboot it and it went wrong, it restart in cycle, enter TWRP, in TWRP they are some process runing on a window and it restart the same.

So, it is flashed, it boot in fastboot and TWRP.
But the problem is that i always can't mount the /data partition.
So, i think i can't restore the backup(same situation).

I am relay not used to the smartphone world.
So, for me it is more magic than anithing, because i don't understand in depth what i'm doing.
So, when you say to flash the Unlocked Bootloader,
Does it mean: fastboot flash bootloader Unlocked_bootloader_pro5_update.zip

Actually, i have another problem, i can't mount the data partition and the internal storage has a 0 mb value.
So, duckduckgoing i see that it may be a corrupted /data partition.
And some people have fixed it with fastboot format userdata. I tried, it didn't work.
the error was: Formatting is not supported for file system with type ''.
When looking man fastboot i see this: fastboot format[:[fs type][:[size]] partition.
So, fs type, maybe ext4 but the size?

OK, thank you very much.

So, i unzip the archive and i put it on the phone to be restored, is it?