When you enable the Sentinel Repositories feature, it will create some workflow files in your GitHub and you should see the executions of the deployment on the 'Actions' page in that GitHub.
The first thing to do would be to go to that page and try to find an error or warning message that explains why the given rule was not deployed.
You have not provided any details in your question, so at this point I can only guess. Some of the things that could have happened:
1: When you configured the Repositories feature, you have not picked the Analytics rule deployment.
2: Your Analytics rule is not in the correct format (it should be a json-formatted ARM template, not the YAML file from the official Sentinel repository)
3. Your rule is simply not a valid JSON file or rule file.
There can be lots of smaller things as well, but these are the most typical ones I've encountered during troubleshooting sessions.