required dynamichidden email field

I am currently using custom post types for “stores”, which have a custom contact mail address field.
I’d like to send the contact mail to the custom field ’email’.

So it looks like this in my CF7-form configuration:
[dynamichidden store-contact “CF7_get_post_var key=’email'”]

In the mail-configuration in the recipient field it is (also visible in the selectable fields):
[store-contact]

Unfortunately I get a syntax error and no mail is sent. As soon as I replace my custom-recipient with a fixed address, everything works. I also receive the custom-mail in my body, if I include it there, so it is filled correctly.

I think I have problems as the recipient-fields needs to be a required field maybe? with dynamichidden*, it is not working either ??

Thanks in advance for help.
Greetings