I am trying to apply for a payment plan in the irs website but it says I’m not eligible. Why would that be? I appear to meet the requirements listed on the site.

[DawnC]

Have you had a payment plan before?  If you are ineligible for a payment plan through the Online Payment Agreement tool, you may still be able to pay in installments.   Individuals can complete Form 9465, Installment Agreement Request

If required in the instructions, please attach a completed Form 433-F, Collection Information Statement PDF.   Mail your forms to the IRS - use this link.

If you prefer to apply by phone, call 800-829-1040 (individual) or 800-829-4933 (business), or the phone number on your bill or notice

If you are unable to revise an existing installment agreement online, call us at 800-829-1040 (individual) or 800-829-4933 (business).

See IRS Payment Plan Help page