Most common error in mysql database during the access.
Execute below script on mysql shell for resolve the error.
Note : Modified below script as per your requirement and add SCHEMA NAME, USERNAME & PASSWORD.
mysql> GRANT SELECT ON `SCHEMANAME`.* TO 'USERNAME'@'localhost' IDENTIFIED BY 'PASSWORD' WITH GRANT OPTION;
Query OK, 0 rows affected (0.01 sec)
mysql> commit;
Query OK, 0 rows affected (0.00 sec)
mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)