Hi, this common problem is caused by your Odoo instance that has no permission to connect to your postgresql so it cannot write data into it.

If you have access to your server backend (linux) you can try to go to login to root and then go to the /etc/odoo/odoo.conf and see the username that used for connection by looking for the db_user as picture below

at example above, the db_user use "odoo" username to connect to postgresql. Now, you can try to access postgresql by exiting this code editor by pressing ctrl + x + y, then switch your user to postgres user by typing in 

su - postgres

later on you can type in psql to access the postgres. Now, type this line by line to grant access to that odoo user

ALTER USER odoo WITH SUPERUSER;
ALTER USER odoo WITH CREATEROLE;
ALTER USER odoo WITH CREATEDB;
ALTER ROLE odoo VALID UNTIL 'infinity';

After that restart your server and see if its able to restore

Best regards,

Altela (altelasoftware.com)