Problwm with replying to messages coming from contact form

Hello,

I have a few sites, which use Jetpack contact form and Easy WP SMTP, all configured just the same way (one hosting, the same email application for all). They all work perfect, except one, where an annoying problem occurs.

The problematic site works like this:
When a customer sends a message through the contact form, it lands in my inbox under his name and email address – it is ok. But when I click on “reply”, the recepient email is my own address, so I send the reply to myself instead of send it to my customer.

Of course I can change the address manually everytime when creating email, but this is not the solution I search for. All my other sites work good. I tried to find any difference in configuration between the sites, but with no success – the Easy WP SMTP plugin, as well as Jetpack, are set the same way.

One more thing – the problem started to occur after rebuilding the site, so I suppose I broke something…

Could you please help me locate the problem?

All the plugins are up to date.