As you may know BCH has legacy addresses and new format which starts with "bitcoincash:"
In Crypto APIs, we support both in all endpoints but when you subscribe for a webhook for a legacy address and there is a transaction for the same address but with the new format we didn't send you a callback.

Now, we send you a callback for such transactions as well and to avoid any confusing on your side we send the "originalAddress" in the response.

Here you can see all details: https://docs.cryptoapis.io/rest-apis/blockchain-as-a-service-apis/bch/index#webhook-notifications