A user with two faces?

[A_Man_Without_Clue <love.chaser@gmail.com>]

Hi all,

I am encountering mysterious phenomenon with Buster/LXDE.
Seems like my user account has two identities.

One day I log into my account, do some work, for instance I copy files
to one directory or I install an application software then logout,
shutdown or reboot.

I will login again with same account then I would find the files I had
copied are not there, or an application software I had installed wasn't
there...at all.

I logout, reboot or shutdown.

I login again then I would find those files are in fact in a directory
where I had copied. The software is installed.

As if there are two users with same account.

What is really going on with this?

I really have no clue.....