Why am I not receiving contact enquiry emails from my store?

Hello All,

One of my client is facing an email delivery issue in store. The enquires emails are not receiving on my clients email id.

To debug the issue I have tried below solutions:

  1. Tried to change client email address to my gmail address but it didn’t work.
  2. Set up another demo store and tried in that after importing current theme running on the live theme and it worked.
    I do not understand the issue exactly it from domain or from code.

Can anyone have any suggestion how can I debug the issue .