Yes, Mansfield has a city income tax and has a mandatory filing requirement.

Since you both live and work in Mansfield, your employer has been withholding the correct amount of tax (see boxes 18-20 on your W-2). You don't owe any back tax for all those years you didn't file.

Mansfield administers it's own tax system. That CCA special membership is collection procedure only.

I suggest you contact the city to see what they want you to do. Some cities, like Cincinnati & Toledo, do not require you to file if the exact amount is withheld. It may be that Mansfield is doing that, unofficially. They probably know you live in the city from the withholding your employer submits.

City web site: http://www.ci.mansfield.oh.us/departments-sp-783975672/income-tax-division.html