what is the best way to pay off $15000,00 in debt due too unpaid taxes from 2019, 2020, 2021 and 2022. I expect this debt to be deducted by $6000 due to 2024 return

I set up an installment plan, but for some reason IRS is not being able to withdraw the installments from my account, and I also submitted an offer in compromise form, but haven't paid the application fee or 20% initial offer because I have a guess it will be denied because my current financial situation is much better than when I could not pay for these taxes.