The problem here is that you do not see the visitor's name and email address in the "From" header of the email that you get from your form.
The most likely cause of this problem is the naming of the email field on your form. It must be named
<input type="text" name="email">
This is the input box on the form where the visitor types in their email address. This is the only way the system has of knowing their email address, and it uses this value to make the "From" header for the email sent to you. The form processor expects this variable to be named as above. If it has any other name, it will not show it as the "From" address.
Equally, to see the visitor's name in the "From" header of the email, you must use an input on your form with the name
name (lower case), like this:
<input type="text" name="name">
You will also get this problem if the visitor does not enter an email address on the form (with the Pro service you can make the email address a required field). In such a case a default FormToEmail email address (firstname.lastname@example.org) will be shown, which cannot receive replies.