Hi,
This is due to system-defined threshold policies. https://library.netapp.com/ecmdocs/ECMP12406790/html/GUID-F76DC60C-852E-485D-91E7-A88683AF6C55.html
To not receive notifications through email when this condition occurs, from the GUI perform the following steps:
Navigate to Configuration ---> Event Handling --> System Defined Threshold Policies, from the GUI.
Under Warning Events, uncheck Send alert notifications to.
If this post resolved your issue, help others by selecting ACCEPT AS SOLUTION or adding a KUDO.