Under Organization > Configure > Settings you can configure the security options, but I'm not sure if it's used for guest users too.
![alemabrahao_0-1674859431219.png alemabrahao_0-1674859431219.png](https://community.meraki.com/t5/image/serverpage/image-id/27977i955C10F3BC3F22E1/image-size/medium?v=v2&px=400)
And, unfortunately, it is not possible to delete it automatically, you can only set the password expiration.
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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