If your MySQL or MariaDB backup fails and your error says something like: User has insufficient privileges to SHOW CREATE FUNCTION...
Then the database user you are using doesn't have sufficient permissions to dump database with stored procedures.
If you are using MySQL v5.x then you can run following code.
GRANT SELECT ON mysql.proc to 'YOUR_DATABASE_USER';
If you are using MySQL v8 or one of the latest MariaDB then you can run following code.
CREATE USER 'YOUR_DATABASE_USER'@'BACKUPSHEEP_ENDPOINT_IP' IDENTIFIED BY 'YOUR_DATABASE_PASSWORD';
GRANT ALL PRIVILEGES ON YOUR_DATABASE_NAME.* TO YOUR_DATABASE_USER@'BACKUPSHEEP_ENDPOINT_IP' WITH GRANT OPTION;