Fresh-installation laravel project can't access postgresql database but can do php migrate
Check your database.php file in config directory, and check the pgsql array. If accessing DB credential values from .env not worked there, test it by directly putting credentials there. hope it will help. Artisan commands work by accessing the credentials from .env files directly,not from database.php that's why migration worked.
I had a similar problem, my generated password contained the character: '#'. This made it a comment line, ignoring the rest of the password. I just changed my password.