A Roth 401k and a Roth IRA are not the same thing. With your Roth 401k, you contributed through work and that contribution is done. If you wish to contribute separately to an Roth IRA, that limit is $5,500 ($6,500 if over age 50).
If you don't want to contribute the amount to an IRA, delete your entries.
https://www.irs.gov/retirement-plans/roth-comparison-chart
