public function generateOtp() {

		$this->otp = random_int( 100000, 999999 );

		$valid = DateUtil::getDateTime();
		$valid = strtotime( $valid ) + Yii::$app->core->getOtpValidity();

		$this->otpValidTill = DateUtil::getDateTimeFromMillis( $valid );

		return $this->otp;
	}