Hello Sawan,

Actually Dokan plugin is not responsible for this issue. You can check by disable the dokan plugin and create a new order, reset the password for a test and see what happen. You must see email will not work.

I told you earlier that no user are facing this matter right now. But dokan is child plugin and its parent plugin is woocommerce.

This issue is very common for woocommerce.

Can you please change this site to another server and see what happen.

Thanks