Set email status from API V1

I already have authorization for all contacts I create on Keap via API.
For all contacts that I create on Keap via API I already have authorization, because they are all contacts who have registered on my web platform and have already given me consent to receive my emails.

When i create new contact in Keap from V1 API, I add this param in json data:
"opt_in_reason: “Iscrizione al servizio di

bud email status in Keap si ‘unconfirmed’, where is the problem?

I think there might be some confusion about what the various email address status states are. Our v2 endpoint has some documentation around it: Keap REST API

Essentially, email address statuses are either Marketable or Unmarketable. Within those two buckets are a bunch of different states, based on how the email was added, how it has performed and actions taken by that contact.

When an address is first added, it is in the Unconfirmed state, which is a Marketable state describing an address with which we have no affiliated history or actions. You may send marketing emails to that Contact, but unless you perform an Email Confirmation sequence in the Automation Builder, we can not confirm that they actually did explicitly ask to be marketed to (and change the status to Opt-In), but the actions you can take in either state are the same.

If they instead click the unsubscribe link in an email we will change the status to List Unsubscribe, and no longer permit marketing to be sent to that email. Various other situations may result in addresses becoming non-marketable, such as bouncing emails off the inbox.