Your normal password only works on InfoPeak itself. Apps like iPhone Mail, Outlook, Thunderbird, DAVx5 or Windows Explorer sign in with a device code made for that app. If you lose a phone, you delete its device code and the phone loses access, without you changing your own password.
Create one
- Open Settings → Security → Device codes.
- Give it a name you will recognise, such as "iPhone".
- Under What this code can be used for, choose access for each service: Read, change and send, Read and change, Read only or No access. A calendar app has no reason to also send mail.
- Confirm with your InfoPeak password and copy the new device code into the app. It is only shown once.
The username in the app is always your full email address.