Detail documentation about the API is here:
https://api-docs.ittell.com.ua/docs/en/call2fa/v1
We have integration with 1C, to get more information about this, write on our email vip@ittell.com.ua or in a general chat in Telegram.
Write to our email vip@ittell.com.ua, we will promptly respond, help with a solution.