This issue is resolved in NSX 3.2.3 available from the VMware Customer Connect portal.
Workaround:
GM Site 1
GM Site 2
First determine the current state on both GMs.
In this example we have verified that site1 should be ACTIVE and the following proccedure is used to reset the state of site2
1) remove extra resource (not doing anything from site2) on site2 GM:
DELETE https://site2/global-manager/api/v1/global-infra/global-managers/site1
2) site2 is changed from ACTIVE to STANDBY using internal API (and do NOT change any field name as it is intentional to send the request exactly in this manner:
ssh as root user to site2 GM (This API is internal and must be run directly on the GM:
curl -X POST -ik http://localhost:7441/api/v1/sites?action=set_global_manager -H "Content-Type: application/json" -d '{"status":"STANDBY","force":false,"federation_id":"","gm_name":""}'
If this does not work the force option can be tried
curl -X POST -ik http://localhost:7441/api/v1/sites?action=set_global_manager -H "Content-Type: application/json" -d '{"status":"STANDBY","force":true,"federation_id":"","gm_name":""}'
3) On site1 Active Site, from the UI onboard the site2 GM to STANDBY