Hi Ahmed,
the thing is that the reversal log (during TPM10 run) does not contain the reversal document as it is used in financial accounting (trans. TBB1); instead it displays the original line items once again because the Transaction Manager considers the reversal as a new status of the original business transaction. however, after you execute reversal (via TPM10 Productive run), you can run a standard report TPM20 to see evidences, that your initial accounting entries were actually reversed - there should be both accounting entries - 1) representing initial posting and 2) reversal of initial posting.
I would suggest you once to try that process (including reversal) in some test environment to get familiar and comfortable with the way reversal works in SAP TRM.
hope it will help you.
Kind regards,
Renatas