Why jiraIssueClient.updateIssue() does not update the Issue?

[bstf]

We have a test Jira server on our premise and on customer's. I am using jira-rest-java-client to create and update tickets. Maven deps

<dependency>
   <groupId>com.atlassian.jira</groupId>
   <artifactId>jira-rest-java-client-api</artifactId>
   <version>5.2.1</version>
</dependency>
<dependency>
   <groupId>com.atlassian.jira</groupId>
   <artifactId>jira-rest-java-client-core</artifactId>
   <version>5.2.0</version>
</dependency>

On our test Jira (v8.15.0 Data Center), when I want to do an jiraIssueClient.updateIssue() this works accordingly.

However, on customer's Jira (v8.15.0 Server), with the exact implementation, this call does nothing. The ticket is not updated, no Exceptions are thrown, and because of the Promise<Void> there is no way to check whether it completed OK or not.

We checked the config edit screens and permissions system but found nothing unusual. Basically the configuration on the project is identical in both systems.

Is there something else that we can do before dropping the jira-rest-java-client library and going for a custom http client?

Thanks

[bstf · Accepted solution]

Problem was that jiraIssueClient.updateIssue(key, issue).claim() was missing.

The fact that it seemed to work on one system and not on the other is still mysterious.