The plugin sees that the version label was not updated, but it still marks it as successful:
Environment Status is 'Ready'. Moving on.
Updating environmentId 'e-abc123' with Version Label set to '105576221-newversion'
Checking health/status of environmentId e-abc123 attempt 1/3
Versions reported: (current: 109903707-newversion, underDeployment: 105576221-newversion). Should I move on? false
Checking health/status of environmentId e-abc123 attempt 2/3
Versions reported: (current: 109903707-newversion, underDeployment: 105576221-newversion). Should I move on? false
Environment Status is 'Ready' and Health is 'Green'. Moving on.
Deployment marked as 'successful'. Starting post-deployment cleanup.