public function validateMobileChange( $attribute, $params ) {

		if( !$this->hasErrors() ) {

			$properties		= CoreProperties::getInstance();
			$existingUser	= self::findById( $this->id );

			if( isset( $existingUser ) && $existingUser->mobile !== $this->mobile  && !$properties->isChangeMobile() ) {

				$this->addError( $attribute, Yii::$app->coreMessage->getMessage( CoreGlobal::ERROR_CHANGE_USERNAME ) );
			}
		}
	}