Login issues

[B8H8D8]

Hi.
On my Samsung tablet S7+ I installed Termux + proot-distro + Arch Linux ARM + KDE Plasma.
As root I created a user named in the following "USER" :
$this->bbcode_second_pass_code('', 'useradd -g wheel -c 'my name' -s /usr/bin/bash -m USER')
and give it a password, say "X".
I can do "su USER" and I am logged without giving my password, but if I try to do "login USER", the system asks me a password and when I answer "X", it is systematically rejected.
I could log me using su but if, as a user, I launch a KDE session and the Login screen is displayed after a while, my password is not recognized. I have to disconnect from the VNC viewer. This kill the session and I must restart from the beginning.

Various experiments with logins
$this->bbcode_second_pass_code('', '
0) u0_a290@localhost ... [~] : is the initial login in Termux

1)
u0_a290@localhost 20220107 14:31:20 946 [~] : proot-distro login --user USER archlinux
USER@localhost 20220107 13:31:23 501 [~] $ login USER
=> NO PASSWORD ASKED
USER@localhost 20220107 13:31:35 501 [~] $ su USER
Password:
=> PASSWORD ASKED AND RECOGNIZED
[USER@localhost ~]$
=> LOGGED AS USER

2)
u0_a290@localhost 20220107 14:32:38 946 [~] : proot-distro login --user root archlinux
root@localhost 20220107 13:32:46 1176 [~] # login USER
Password:
Login incorrect
=> PASSWORD ASKED BUT NOT RECOGNIZED
root@localhost 20220107 13:33:34 1176 [~] # su USER
=> NO PASSWORD ASKED
[USER@localhost root]$
=> LOGGED AS USER

3)
u0_a290@localhost 20220107 14:34:38 946 [~] : proot-distro login --user alarm archlinux
[alarm@localhost ~]$ login USER
=> NO PASSWORD ASKED BUT NO LOGIN
[alarm@localhost ~]$ su USER
Password:
=> PASSWORD ASKED AND RECOGNIZED
[USER@localhost alarm]$
=> LOGGED AS USER
')

Please, do you know if there is a solution to this Login issue ?

Thanks for your help.