I have a wordpress website , [login to view URL] and we need to enable the click to call functionality through an API from the likes of exotel or knowlarity.
Sample API will be provided by the telephony provider, we need to modify it for our website and integrate on our website.
All calls initiated should run for a pre-defined duration only, this has to be an inbuilt feature in the API call. The duration would depend on the agent's per minute call rate and total balance in caller's website's account wallet.
For better understanding of the service required, I am attaching a screenshot of the service from one of the competitors.