A code H Form 1099-R must always have a zero in box 2a and box 2b Taxable amount not determined unmarked; direct rollovers from a designated Roth account in a qualified retirement plan like a 401(k) are always nontaxable and the payer should know that. Are you sure that the 2b box that is marked is not the Total distribution box?
Enter $0 in box 2a and it won't matter if you mark box 2b Taxable amount not determined or not.
