Acrobat not prompting me to select a response file when forms returns

[Alex Hammerstein]

I have created a distributable form which I have sent to the recipients.  A responses.pdf form was created at the same time.    When users are returning forms, they are arriving by email but embedded in the email not as an attachment.    I am puzzled as to how I am able to get the data into the responses pdf file?     I have tried saving the email as a pdf file, but that didn't work.

Any help much appreciated.

Using MacOS Big Sur and Apple Mail.

Thanks