It sounds like you may have been trying to set up an installment plan with the IRS.
See: https://ttlc.intuit.com/community/after-you-file/discussion/how-do-i-get-a-copy-of-the-acceptance-le...
or
https://ttlc.intuit.com/community/taxes/discussion/how-can-i-file-an-installment-agreement-if-i-alre...
and
https://turbotax.intuit.com/tax-tips/tax-payments/facts-about-irs-payment-plans/L1zHPFVDI
https://ttlc.intuit.com/community/tax-payments/help/can-i-set-up-a-payment-plan-for-my-taxes/00/2651...
