Error Installing Tiny Tiny RSS

Hi!
I tried to install Tiny Tiny RSS. After download and install, i got an error

Fehler beim Installieren der Anwendung: (‘ttrss’, ‘’, ‘Traceback (most recent call last):\n File “/usr/share/plinth/actions/ttrss”, line 157, in \n main()\n File “/usr/share/plinth/actions/ttrss”, line 153, in main\n subcommand_method(arguments)\n File “/usr/share/plinth/actions/ttrss”, line 103, in subcommand_enable_api_access\n password=password, host=host)\n File “/usr/lib/python3/dist-packages/psycopg2/init.py”, line 130, in connect\n conn = _connect(dsn, connection_factory=connection_factory, **kwasync)\npsycopg2.OperationalError: FATAL: password authentication failed for user “ttrss”\nFATAL: password authentication failed for user “ttrss”\n\n’)

If i try to start the application i got this answer

Exception while creating PDO object:SQLSTATE[08006] [7] FATAL: password authentication failed for user “ttrss”
FATAL: password authentication failed for user “ttrss”

What can i do?