Penalty for converting traditional IRA to Roth IRA

My husband converted $16,000 from a traditional IRA to a Roth IRA.  We realize we owe taxes on this amount. However, after having several Turbo Tax people share my screen and watch how I entered all of the necessary information, I get a message that says we will have to pay a 6% penalty for contributing too much to the Roth IRA. It was not a contribution, it was a conversion. We were told we would not have to pay a penalty for converting this money.