Azure Database for PostgreSQL flexible server: password authentication failed

Good afternoon,

I am using an Azure Database for PostgreSQL flexible server with no public
ip.

It is connected to a private VNet and I try to access it from an Alpine
Linux container with openssl and postgresql-client installed.

In Azure portal I have clicked the "Reset password" button, entered
twice password12345!! and received the web browser notification
"Successfully reset the password for postgresql"

Then I run the commands:

$ openssl s_client -connect 172.21.32.4:5432 -starttls postgres
(then after some time)
2C820000:error:8000274C:system library:BIO_connect:Unknown
error:../openssl-3.2.3/crypto/bio/bio_sock2.c:178:calling connect()
2C820000:error:10000067:BIO routines:BIO_connect:connect
error:../openssl-3.2.3/crypto/bio/bio_sock2.c:180:
connect:errno=0

$ PGPASSWORD="password12345!!" psql "postgresql://postgres:password12345!!@
172.21.32.4:5432/postgres?sslmode=require"
psql: error: connection to server at "172.21.32.4", port 5432 failed:
FATAL: password authentication failed for user "postgres"

In the server logs I see entries for some other connections:

2025-02-28 14:39:35 UTC-67c1ca93.50ee-LOG: disconnection: session time:
0:00:20.024 user=azuresu database=postgres host=169.254.128.1 port=53076
2025-02-28 14:39:36 UTC-67c1caa8.5146-LOG: connection received:
host=169.254.128.1 port=49016
2025-02-28 14:39:36 UTC-67c1caa8.5146-LOG: connection authenticated:
identity=\"CN=azuresu.c1fba9900d4d.database.azure.com\" method=cert
(/datadrive/pg/data/pg_hba.conf:17)
2025-02-28 14:39:36 UTC-67c1caa8.5146-LOG: connection authorized:
user=azuresu database=postgres SSL enabled (protocol=TLSv1.3,
cipher=TLS_AES_256_GCM_SHA384, bits=256)

I do not see any logs related to my unsuccessful tries.

In the "Server parameters" I have set the parameters:

log_connections ON
log_hostname ON
log_statement MOD
max_connections 500
ssl ON (cannot change that one)
listen_address '*' (cannot change that one)

And currently I am stuck, wonder how do others debug such problems?

Best regards
Alex