The only way to get an IRS approved payment plan is to apply directly to the IRS. There is a non-refundable application fee. Many payment plans are approved instantly if you apply online.
https://www.irs.gov/payments/payment-plans-installment-agreements
https://www.taxpayeradvocate.irs.gov/get-help/paying-taxes/installment-agreements/
It is possible to apply for a payment plan indirectly, using another company, but the application fees are higher and the company applies for you by mail, which takes much longer to get approved.
Is there a chance you actually applied for some kind of loan program where the company pays the tax with a loan and you pay the company back? (I'm sure the interest and fees will be much higher than a direct IRS payment plan.)
I have no knowledge if the company you used is good or bad, but for the other reasons I mentioned, I would never use a private company to request a payment plan, I would only apply online directly to the IRS. That's assuming you want to pay your taxes in full eventually. If you want to negotiate a lower payment (offer in compromise), I would work with a local tax professional, not a national or online company.
