An IRA and a 401(k) are totally different. If you have a retirement plan through a regular W2 job with Code "D" in Box 12 - that's a 401(k), not an IRA.
Do not enter a 401(k) contribution in the program as an IRA contribution. You account for 401(k) contributions by entering your W2 and that's it. Your 401(k) contributions have already been removed from the taxable wages in Box 1 of your W2.
IRA contributions aren't handled through an employer. If you also made an IRA contribution of $5500 outside of employer, enter only that under IRA contributions.