discrepency in balance_trasnsaction definition

[JerryPD]

I am getting a list of orders from a site. As a result, I get Orders[x].

In Orders[1].refunds[0].transactions[0].receips.charges there is an item called balance_transaction. In one order this item is a string, and in another order, this item is an object with child properties. In both cases the transaction is exactly the same type. I was using 2020-10 API, and just changed to 2021-01 API, and I am still crashing when attempting to convert this field.

Has anyone else seen this type of discrepency? I am pretty much clueless as to how to proceed!

subset of code from order 1:

"charge": {
"id": "ch_1IvSX1L7pdTqbdGY4BkUFj6r",
"object": "charge",
"amount": 4742,
"application_fee": "fee_1IvSXAL7pdTqbdGYlYAm7gYj",
"balance_transaction": "txn_1IvSXAL7pdTqbdGYjqUbBd59",

subset of code from order 2:

"charge": {
"id": "ch_1J0rJFL7pdTqbdGYfAr80Bqv",
"object": "charge",
"amount": 8154,
"application_fee": "fee_1J0rJGL7pdTqbdGYOPfa8kNp",
"balance_transaction": {
"id": "txn_1J0rJGL7pdTqbdGYc0Q5WfJY",
"object": "balance_transaction",
"exchange_rate": null
},