Ensure you have Retreaver Number Pools and the Retreaver JS installed on your landing page first
In Campaign set up after selecting Retreaver (Native) as your call tracking platform click "Add account"
In Retreaver, get your API key by going to Settings > My Account > API Access
Select "Show" and Copy and Paste your API Key into TrueCall
Click set up in TrueCall
Select the campaign within Retreaver that is applicable
Continue set up and test your landing page by entering in the page that contains the number pool. Your Calls will now be Tagged with the TrueCall ID in Retreaver
Configure a webhook to send the TrueCall ID to your client within Retreaver if needed.