To resolve this, please follow the below steps carefully:
Open "Manage Threshold" window and take screenshot of all mappings (if you remembered them then please skip this step)
Once you deleted the mapping, changes will take approximately 15 minutes for applying. (Node: Please do not shutdown or terminate WM server in between this 15 minutes, this will lead some serious polling issue)
Make sure that you have successfully deleted all mappings. (To verify, just double click on any attribute in which you have previously applied threshold settings. Verify threshold checkbox and threshold list should be unchecked and empty resp.)
Re-map all mappings which you have deleted at step 2 (Take help from step 1)
This will again take approximately 15 minutes to apply the required changes.
Your threshold will be reflected in next polling interval of perticular attribute.
For any other threshold related queries, please mail us: support@cambiumnetworks.com