First find your file
If you don’t know where it is, query the database with the sql: SHOW config_file;
Mine is in: /var/lib/pgsql/data/
Login as root and edit that file.
Search for the string: “max_connections”.
You’ll see a line that says max_connections=100.
Set that number bigger, check the limit for your postgresql version.
Restart the postgresql database for the changes to take effect.