Elasticsearch plugin help

Can anyone please help me with setting up the Elasticsearch plugin for Omeka Classic?

I have installed Elasticsearch on the Omeka server, and it appears to be running correctly.

I installed the Elasticsearch plugin for Omeka Classic.

When I attempt to index in the plugin settings, it runs for 1 second and does not appear to be doing anything.

Any suggestions for where to find the issue, troubleshooting, etc?

Thanks,