While updating Mailcow this morning Docker gave me a "too many requests" error.
It seems that Docker now limits the IPv6’s subnet instead of the IPv6 address itself, which could mean your pull limit is shared.
To fix this you can create a personal account at docker.com, this will allow 200 image pulls per 6 hours. My Mailcow installation does 7 pulls for an update.
Once the account created, copy the personal access token, go back to your server and enter docker login -u (login)
Mailcow will now update without error.
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