do you have pay stubs that show year-to-date withholding with the final paystub agreeing with what's on the w-2? do you have other withholding sources?
if so, take the pay stub for wages paid on or before 3/31. that will be the withholding through 3/31. then take the paystub on or before 5/31 and subtract the previous withholding. thta's the withholding for the 2nd quarter. do the same for the 8/31 paystub
if you have other sources of withholding, you'll have to determine to which period they apply and add it to the above.
if your w-2 withholding doesn't agree with the final 2024 paystub, contact your employer.
if your situation is different then provide sufficient information to allow us to provide guidance or a solution.