The log can be opened from the Sales Order by using the Related / Payment Gateway Log action or directly when you search for Payment Gateway Log page. This page is used to check the details of the payment/transactions.
The Payment Gateway Log shows the details of the payment(s) taken, their outcome (Payment Status), the Payment Amount received.
All transactions have a unique Transaction ID which used to identify the transaction.
At this point there is a record of a payment into the system but cash receipt is not yet posted, the Cust. Ledg. Entry No. is 0 as payment ledger is not posted. Post the Sales Order.