You can simply use Change Passwords API explained here: Change passwords API | Elasticsearch Reference [7.11] | Elastic
If you do not have any access to change your password, you can create a superuser, login with that user and then change your password using the command-line API or Kibana UI itself. As the document says: Create or update users API | Elasticsearch Reference [7.11] | Elastic
You will need to provide your username password in kibana.yml to access your dashboard as well:
[...]
elasticsearch.username: "username"
elasticsearch.password: "your_password"
[...]
This also might help you: I lost the password that has been changed