Sign-up confirmation is mandatory when using the MailPoet Sending Service.

Hi there @al2min,

As mentioned in the screenshot, if you are sending with our MailPoet Sending Service then the double confirmation is required and cannot be disabled:
https://kb.mailpoet.com/article/128-signup-confirmation-double-opt-in-feature

The only way to disable it would be to send with your own sending method:
https://kb.mailpoet.com/article/135-the-send-with-tab