When the backup schedule is disabled in the NSX UI, the setting reverts (rolls back) to the enabled state after approximately 5 minutes.
VCF 9.0.1
This issue occurs because SDDC Manager periodically checks the backup configuration (every 5 minutes).
If SDDC Manager detects that the NSX backup schedule is disabled, it automatically resume (re-enables) the schedule to enforce the configuration.
This issue was fixed in VCF 9.0.2.
Workaround
To work around this issue, modify the SDDC Manager configuration to disable this enforcement behavior.
su - vim /opt/vmware/vcf/lcm/lcm-app/conf/application-prod.properties lcm.nsxt.backup.wait.timeout=0systemctl restart lcm