from email dont work well

Our customer have some trouble with their email. When they get an email they get it from their own email, this is a bit strange but i think this comes true the from field [your-email] <[email protected]>. But this is why we set up the reply-to field like this: Reply-To: [your-email]. but it seems that this is not working well. when he is clicking on his iphone on the bottom reply icon he emails back to himself and when he clicks into the specific email on send then he email back to the customer. so its really strange, how can we change this solution so he emails back to the customer on both of the option?

here is a link to my setting: https://ws-exhaustsystems.nl/wp-content/uploads/2022/01/Schermafbeelding-2022-01-31-om-18.51.48.png

The page I need help with: [log in to see the link]