Best answer
Collecting an email in a DM is lawful in the same way a form on your site is lawful: you need a reason, you have to say what you will do with it, and the person has to be able to get out.
Nothing about the chat surface changes the obligations. What changes is that people read less carefully in a chat, so the wording has to carry more weight in fewer words.
What to do in the flow itself:
- Say what the email is for before you ask. "Send me the PDF" is one purpose. Adding them to a weekly list is a second one and needs its own yes.
- Make the choice explicit. A button they tap is evidence. A message they ignored is not.
- Store the consent, not just the address. A tag or a custom field with the date is what you show if anyone asks later.
- Give them a way out in the message that delivers the thing, not only in the fifth message.
What the platform does for you: STOP unsubscribes are honoured automatically across channels, and a contact's data can be exported or deleted on request without going through us. The data export and deletion path is in the privacy policy.
One thing that is genuinely different from a web form: people often type an address with a typo because they are on a phone. Validate the field in the flow and ask once more rather than sending the PDF into a void and recording a lead that never existed.