Explanation
https://docs.vmware.com/en/VMware-NSX-Intelligence/1.1/user-guide/GUID-EBD3C5A8-F9AB-4A22-BA40-9
"If you move an alarm into a Suppressed state, you are prompted to specify the duration in hours. After the specified duration passes, the alarm state reverts to Open. However, if the system determines the condition has been corrected, the alarm state changes to Resolved."
https://docs.vmware.com/en/VMware-NSX-T-Data-Center/3.0/administration/GUID-EB1BB1D3-8892-4890-BE