Como resolver o rrro do PgAdmin no Ubuntu 22 "FATAL: password authentication failed for user"

 Run the following commands:

sudo -i -u postgres

Input your sudo user password

psql
ALTER USER postgres PASSWORD 'new_password';
\q
exit

Now change config file to use this new password:

sudo subl /etc/postgresql/13/main/pg_hba.conf

(subl means subliime text, you can use any other text editor).

Edit this part of the file: change peer to md5

# Database administrative login by Unix domain socket
local   all             postgres                                peer

# "local" is for Unix domain socket connections only
local   all             all                                     peer

restart the postgres service

Run this command to sign into postgres using the newly created password:

psql -U postgres