微信小程序插件OCR报错，已经购买过了,但是一直报错VM4964:1 invokeService fail Error: invokeService:fail operateWXData:fail (err_code -2)

代码片段：   // 这里调用小程序插件OCR

        wx.serviceMarket.invokeService({

          service: 'wx79ac3de8be320b71', // '固定为服务商OCR的appid，非小程序appid',

          api: 'OcrAllInOne',

          data: {

            img_data:data.url,

            data_type: 3,

            ocr_type: 1,

          },

        }).then(res => {

          console.log("ocr==》",res);

          console.log('invokeService success', res)

          wx.showModal({

            title: 'cost',

            content: (Date.now() - d) + '',

          })

        }).catch(err => {

          console.error('invokeService fail', err)

          wx.showModal({

            title: 'fail',

            content: err + '',

          })

        })