To  collect name, email and phone number from your contact -  follow the steps and add these lines directly into your prompt. 


Lets say you want to collect name , email , phone
Add this in the prompt to make sure the bot asks these questions 
Start the prompt from ### mandatory instruction 

###mandatory instruction : before booking an appointment always start the conversation by asking these question one after another
1. Ask the customer his name 
2. Ask the customer his email
3. Ask the customer his phone


Example.