error issue

pts={{0, 1, 2}, {1, 0, 3}, {4, 5, 6}, {5, 4, 7}, {8, 9, 10}, {9, 8,
  11}, {12, 13, 14}, {13, 12, 15}, {16, 17, 18}, {17, 16, 19}, {20,
  21, 22}, {21, 20, 23}, {24, 25, 26}, {25, 24, 27}, {28, 29,
  30}, {29, 28, 31}};

polys= {{0, 1, 2}, {1, 0, 3}, {4, 5, 6}, {5, 4, 7}, {8, 9, 10}, {9, 8,
  11}, {12, 13, 14}, {13, 12, 15}, {16, 17, 18}, {17, 16, 19}, {20,
  21, 22}, {21, 20, 23}, {24, 25, 26}, {25, 24, 27}, {28, 29,
  30}, {29, 28, 31}};