Brevo Integration

Please help. I have configured the contact form with checkboxes which correspond to the list names in brevo. I can submit the form and it will populate with name phone etc, but no opt_in is accepted at the brevo end. No lists are populated. I dont want the contact form to populate every list, I just want it to populate the list that my enquirers choose to belong to by ticking one or more of the checkboxes. Radio boxes are not working to populate either. Brevo expects an item number here rather than the actual name. There doesnt seem to be a way to get contact form 7 to issue the field in terms of the number of the list. ie Been before translates to number 1, Facebook is number 2 etc.

When the form is submitted to me as an enquiry, the full text version of the field is needed so I can help my customer rather than just saying number 1 from the radio list.

I have tried to add in an integromat (make) go between to try to see if that talks to brevo better but that is failing also so that has been a waste

I have spent many many days on this and worked through all the help files but non seem to apply to my issue.

The emails I am using as my test customers to verify the brevo list inclusion are new contacts.

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