Users unable to add new custom metrics using the database monitoring tool may see the following error displayed in the Controller UI:
Error message
This issue occurs when the default limit for database monitoring has been reached.
By default, database monitoring supports up to 20 custom metrics per database. When this limit is reached, the tool will not create any new custom metrics and the above error is displayed.
To resolve this issue, the user can configure the following property to a higher value.
admin.jsp
page and change the following property value:dbmon.config.max.custommetric
Configure custom metrics
Thanks for share the link, But i already used this steps but still showing the alerts.