Seamless.AI has a native integration with Salesforce, however SF Professional and SF Essentials require a different set of steps to integrate with Seamless.AI.
Salesforce Professional and Salesforce Essentials have limitations on their API access, which is required to directly integrate Seamless.AI + Salesforce.
SF Professional - This requires an additional API Package to be purchased. For Salesforce Professional users, please contact your account manager to active the API package so you can integrate directly with Seamless.AI. You can find more information on this here.
SF Essentials - Salesforce Essentials does not offer an API package, however Seamless.AI directly integrates with Zapier. Zapier offers an integration with SF Essentials so you can integrate directly with Zapier and have this information port directly into Salesforce. You can find more information on this here.