EvoDesign freezing residues

For my protein-peptide interface project, I want to prevent EvoDesign from mutating residues 25-35 in my protein (I want the residues to remain the same in my scaffold and design proteins). As such, I entered '25,26,27,28,29,30,31,32,33,34,35' in the "freezing some residues" field. The results seem to indicate that positions 25-35 were nonetheless mutated to be different from the input scaffold. Any help is most appreciated.