Your email account needs to have the same password as your Nextcloud account. Currently this means that you have to change your password in two places in order to update your password. This is something that we are working to simplify for our next update.
The following characters are allowed in passwords: A-Z a-z 0-9 . - _ @ # $ ^ & + = ? ! *
The settings for auto reply for your email account can be found by logging into our email providers mail client at mail.glesys.se. Use your full email address and your original Nextcloud password. Go to Account settings in the main menu and scroll down to Change password.