My annuity had matured so I was told I would not have a penalty.

We'd love to help you complete your tax return, but need more information. Can you please clarify your question?

What code do you have in box 7 of your 1099-R form?

Did you take it out?  You might not owe a early withdrawal penalty to the annuity plan but it may be taxable and a 10% early withdrawal tax penalty if you were under 59 1/2.   What code is in box 7 ?  Did you move it to another account like a IRA?