同样的参数，昨天生成小程序直播码可以，今天就不行了，请帮忙查下什么原因？

使用API创建二维码： https://api.weixin.qq.com/wxa/getwxacode

小程序APPID ： wxec78156626302b78

携带的参数

{"path":"plugin-private://wx2b03c6e691cd7370/pages/live-player-plugin?room_id=10&type=9&custom_params=%7B%22FromUserId%22%3A%22johnswang%22%7D","width":430,"auto_color":false,"is_hyaline":false,"line_color":{"r":"0","g":"0","b":"0"}}

返回错误，

{"errcode":40159,"errmsg":"invalid length for path, or the data is not json string hint: [uiNcODALRa-DrIf4]"}