HTML form Submit to php cannot POST

html
php

#1

I have a form on my webpage and when I click the submit button I get the error: Cannot POST /vfs/853c91602bab4294adf3225d0be4631a/preview/PLLR%20site/FormSubmit.php

My html form is:

  <form method = "post" action = "FormSubmit.php">
                        
          <legend> Buisness Information </legend> 
                        
                Name <br><input type = "text" name = "name" placeholder = "Your Name" required><br>
                            
                Email <br><input type = "email" name = "email" placeholder = "Your Email" required><br>
                            
                Phone <br><input type = "text" name = "phone" placeholder = "Your Phone Number" required><br>
                            
               Company Name <br><input type = "text" name = "CompanyName" placeholder = "Your Company" required><br>
                             
 <button type = "submit" name = "submit" id = "SendEmail">Send</button>

 </form>

my php is a simple echo statement.
the two files are in the same folder.

thanks for any help