Chat Web Widget does not appear on the help center page

We have done activating this "Add to help center" option in the web widget configuration on Zendesk admin.

But it does not appear on the help center page.

This is the link to our help center: https://support.coins.ph/hc/en-us

Per discussion with Zendesk Support Team, they mentioned that using the custom launcher caused this issue.

I'm confused about where can I put the code to make the chat web widget show on the help center page?

Thank you.