Update docs/configuring-playbook-bot-matrix-reminder-bot.md: add the common section "Troubleshooting"

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

docs/configuring-playbook-bot-matrix-reminder-bot.md

@@ -62,3 +62,18 @@ Basic usage is like this: `!remindme in 2 minutes; This is a test`
 Send `!help reminders` to the room to see the bot's help menu for additional commands.
 
 You can also refer to the upstream [Usage documentation](https://github.com/anoadragon453/matrix-reminder-bot#usage).
+
+## Troubleshooting
+
+As with all other services, you can find the logs in [systemd-journald](https://www.freedesktop.org/software/systemd/man/systemd-journald.service.html) by logging in to the server with SSH and running `journalctl -fu matrix-reminder-bot`.
+
+### Increase logging verbosity
+
+The default logging level for this component is `INFO`. If you want to increase the verbosity, add the following configuration to your `vars.yml` file and re-run the playbook:
+
+```yaml
+matrix_bot_matrix_reminder_bot_configuration_extension_yaml: |
+  logging:
+    # Allowed levels are 'INFO', 'WARNING', 'ERROR', 'DEBUG' where DEBUG is most verbose
+    level: INFO
+```