If you are in Alabama, EX OT in box 14 of your W-2 represents the overtime income you earned in 2024 that is exempt from state tax. The exempted wages should already be reflected in box 16 of your W-2 (state wages). This exemption does not impact your federal tax return.
The exempt overtime isn't subject to tax in Alabama, so it'd ultimately reduce your Alabama taxable income. If box 16 of your W-2 includes the exempt overtime, you will need to contact your employer for a corrected Form W-2.