When we publish a content after fixing the server side mandatory validation errors (postSave api error), it shows up on backoffice server immediately, but not on the front end server.

We have to publish twice in order to display it on the front end server.

And we believe that this is caused by published content index not getting synced over to the front end server, the first time we publish it.

Or the postSave api error blocks the content index sync over to the front end server.

The content should be displayed on both front end and backoffice server at the same time on publishing it for the first time.

We have already followed the load balancing setup from here https://our.umbraco.com/Documentation/Getting-Started/Setup/Server-Setup/Load-Balancing/