The error is reported for MySQL backup or restore.
The MySQL user account, which is used for the DB access, does no have all privilegies on the target database.
Grant the required privileges to the user account for the target database. For that login to the MySQl with root user credentials:
mysql -u root -p
after that grant the privileges:
GRANT ALL ON *.* TO 'root'@'localhost' WITH GRANT OPTION;
Note: refer to Oracle MySQL documents: https://dev.mysql.com/doc/refman/8.0/en/grant.html