diff --git a/ykval-verify.php b/ykval-verify.php
index b012877..7dc8266 100644
--- a/ykval-verify.php
+++ b/ykval-verify.php
@@ -85,6 +85,7 @@ if (preg_match('/^[jxe.uidchtnbpygk]+$/', $otp))
 	$new_otp = strtr($otp, 'jxe.uidchtnbpygk', 'cbdefghijklnrtuv');
 	$myLog->log(LOG_INFO, "Dvorak OTP converting $otp to $new_otp");
 	$otp = $new_otp;
+	unset($new_otp);
 }