使用万能票据2008的查询功能时出现以下提示：
argument 'index' is not a valid value

at
microsoft risua lbasic collection get-item (object index)

at
common class data gridarray get-item (string name)

object reference not set to an instance of an object

at bill billlistui readentrysdata

这是什么原因？如何处理？