Do we have to pay Penalty and taxes? We received a 1099-R for a gross distribution on our Roth IRA with box 2b stating: Taxable amount not determined.

We withdrew the money because our sons Cloverdell 529 plan's balance is only enough to pay for his rent. His tuition was due in August 2018 to the amount of $5,000 plus and the remaining we used to pay the second semester 2019