Hey @Chinmay_Sharma,
ExchangeLineItem doesn’t have createdAt or location fields directly, so you’ll need to grab those from adjacent objects.
For the timestamp, you can use Return.createdAt or ReturnAgreement.happenedAt via order.agreements.
For location, that lives on ReverseFulfillmentOrderDisposition through Return → reverseFulfillmentOrders → lineItems → dispositions → location. One caveat, if “don’t restock” was selected, no disposition record gets created. I covered some workarounds for that in a previous thread.