custom signup form in Magento 2

Hi,

We have a custom signup form in our magento site. It was using the old api api/v2/list/members and we would pass email, first name, last name and consent. 

In the new api I have tried to create a type=profile to api/profiles/ ( https://developers.klaviyo.com/en/reference/create_profile) then add the profile to a list using api/profile-subscription-bulk-create-jobs/ 

I have also tried to just use api/profile-subscription-bulk-create-jobs/ (but do not know how to get the first name and last name in as https://developers.klaviyo.com/en/reference/subscribe_profiles does not show those fields). 

To do it the way we did in v2 would be https://developers.klaviyo.com/en/reference/create_list_relationships based on what I read on the comparison chart but I do not see what data I can pass or how it is expected. 

The first two ways I am trying work to get the user signed up to the list that I specified that is not double opt in, but in both cases it also sends the double opt in for another general list that I did not intend. Any ideas what I am doing wrong ? 

--Vince