Hosting Knowledge Base
“SQL ERROR – INSERT command denied to user…” error appears on my website
It is very likely that your database has gone over quota if your website starts returning error messages like this:
SQL ERROR [ mysqli ] INSERT command denied to user ‘DATABASE_NAME‘@’DATABASE_HOST‘ for table ‘DATABASE_TABLE‘ 
Please note that some of our hosting packages have а quota for the database size. When you reach the disk space quota for a database, the server will reject all INSERT commands.
You can check the disk space quota and current usage for a database from the “Quota” column in the control panel -> Database Manager.
For more information, on what your options are, when your database is over the quota, click HERE.