ajax request submits form twice

[izachia]

Hello,

I am using the next script to submit a contact from but the form gets
submitted twice and the client gets 2 email. What I am doing wrong?

new FormCheck('contactform', {
submitByAjax : 'true',
ajaxResponseDiv: 'responseWrapperContact',
alerts : {
required : 'This field is required! '
}
});