Invoice extraction using document Understanding

I am using document understanding to extract the data from different type of invoices, But I am facing this issue Data Extraction Scope : Index was outside the bound of the array


What part of the code throws this error.
Index was out of range is a generic error and comes when you try to access object that does not exists or your index was out of range. For ex name{“a”,“b”}
Now if you try to access name(2)… it will throw an error, Index was out of boumd.