Contact form values before sending

Hi,
We are using contact form 7 for all contact page and its working fine But recently we have updated our wordpress to latest version and also we have updated contact form to latest version, from there on words the salesforce integration not working
getting the white scree error after checking the error log we got this information
Fatal error: Cannot redeclare becomeastylist_crm() (previously declared in below are the code we used for
add_action( ‘wpcf7_before_send_mail’, ‘becomeastylist_crm’, 10, 1 );
function becomeastylist_crm($cf7)
{
$lead_source = $cf7->title;
$form_id = $cf7->id;
$submission = WPCF7_Submission::get_instance();
$posted_data = $submission->get_posted_data();
/*validating alphanumeric value*/
$first_name = stripslashes($posted_data[“firstname”]);
}
please advice.

Thanks