Whatsapp and Telegram Client for Tourism API

I have an existing system for reservations and purchase of tickets for traveling (transportation and hotels). We need an Instant Messaging Module for 1) Whatsapp (WA) and 2) Telegram (TM), like chatbots, that process the requests in natural language (Spanish) from customers using WA and TG, through text AND voice, and convert the human request to a request to the existing system APIs. And provide the answers in text to the customer. All the backoffice is done through the existing system. This IM new module is just the front to take the request from customers in natural language through WP and TG.