diff --git a/plugins/wporg-5ftf/includes/endpoints.php b/plugins/wporg-5ftf/includes/endpoints.php
index f51601c..1611584 100644
--- a/plugins/wporg-5ftf/includes/endpoints.php
+++ b/plugins/wporg-5ftf/includes/endpoints.php
@@ -92,8 +92,8 @@ function send_manage_email_handler() {
 	check_ajax_referer( 'send-manage-email', '_ajax_nonce' );
 
 	$pledge_id   = filter_input( INPUT_POST, 'pledge_id', FILTER_VALIDATE_INT );
-	$email       = filter_input( INPUT_POST, 'email', FILTER_VALIDATE_EMAIL );
-	$valid_email = get_post( $pledge_id )->{ META_PREFIX . 'org-pledge-email' };
+	$email       = strtolower( filter_input( INPUT_POST, 'email', FILTER_VALIDATE_EMAIL ) );
+	$valid_email = strtolower( get_post( $pledge_id )->{ META_PREFIX . 'org-pledge-email' } );
 
 	if ( $valid_email && $valid_email === $email ) {
 		$message_sent = Email\send_manage_pledge_link( $pledge_id );