You might as well say that the credit was claimed for 4 years, because you are no longer eligible for the American Opportunity Credit anyway. If you have completed 4 years of college you are not eligible for the American Opportunity Credit, even if you didn't claim it for those 4 years.

Didn't TurboTax ask if you have completed 4 years of post-secondary education? If it didn't ask yet, that question might be coming up.

it did ask that, but then came up with two fields to enter how many years the credit was claimed when I selected that it had previously been claimed for me for those four years....I ended up just skipping the page and not entering a value and now it seems to not be bringing it back up/showing that you've pointed out- that I'm not even eligible for the credit as I've completed four years of higher ed...so I suppose the same outcome to entering it was claimed all four years?

You're looking for a "result" too soon.  Just keep going.  You will reach an education summary screen wherein TurboTax (TT) will select either the Lifetime Learning Credit (LLC) or the Tuition and Fees Deduction (TFD) for you, as well as tell you you're not eligible for the  American Opportunity Credit (AOC).