"Start Chat" doesn't display using puppeteer but working fine in by writing script in Selenium. How to fix it in puppeteer?

I'm writing an automated script for a website using Puppeteer. It includes chat feature. In puppeteer node.js script "Start chat " button does not display. IF I run the script in Selenium then "start chat" display on which we can click and start chat as shown in given screenshot.

but running script in puppeteer this "Start chat" button doesn't display as show below.