There are few things we can start looking into:

• Update DBeaver and JDBC Driver: Ensure that you're using the latest version of DBeaver and the Databricks JDBC driver. Sometimes, updating to the latest version can resolve connection issues.

• Check OAuth settings: Since you're using OAuth for authentication, make sure that the OAuth settings are correctly configured in Databricks and that the account you're using has the necessary permissions.

• Try a different authentication method: If possible, try using a different authentication method to see if the issue is specific to OAuth.