contact字段加密之后 返回这个错误 这个是什么原因

<xml><return_code><![CDATA[SUCCESS]]></return_code><return_msg><![CDATA[OK]]></return_msg><nonce_str><![CDATA[IUtsqgtqR1ZvyD89]]></nonce_str><sign><![CDATA[7791B070EE6BCAFACDDC928011C83C440727D23CBF984F83D90166003B200B8D]]></sign><result_code><![CDATA[FAIL]]></result_code><err_code><![CDATA[PARAM_ERROR]]></err_code><err_code_des><![CDATA[联系人姓名长度超过限制，请检查后再试。]]></err_code_des><err_param><![CDATA[contact]]></err_param></xml>

参数是邹洪运 三个汉字 经过加密之后得字符串是ZaolnRv3ouR2dVmGxOL9izxshh1QjCycb/OI6/6bSTJ3uksH63N4nnswH5X3GY4eOQbWOBqETZIVOFL/YN9eCspCxY5OIsQQfTzckLxOTCyn6baNEB79i5m9pNu13bEEWT+YDE66BVX/HXm5ZJTd28cHw/kkkwe20p4k6pkSxt93EYScTwGuJpO9+80Vbp4YnUNYGBPMZZfuw9V2ovcYmShdQqyKetsfJU+N+q3fJlQbxC4xCD8tvfq0qOAsSbCa/5ImM0DyU7ZaDIC0LqaBurawuB2pupD4M7tqyWUHaP/J81oy6W24Een1xdGmmetbL28mqTJHMoMVwHcGZgzoAw==