In this task, you are given an input list A comprising of numbers and alphabets. You need to extract and sort the unique alphabets in the list. The alphabets in the input list will only be in lowercase. Return -1 if there is no alphabet in the input list.

['2247', 'w', 'h', '4675', '6153', 'f', '6029', 'o', 'd', 'j', 'z', 'y', 'i', '6899', '3917', 'u', '6447', '6405', 'a', '1705', '8585', 'v', 'f', 'r']
a, d, f, h, i, j, o, r, u, v, w, y, z

['4749', '4607', '625', '6907', 't', 'b', '8479', '6505', 'r']
b, r, t

['v', 'e', 'd', 'd', '8995', 'l', 's', '4689', '1463', 'd', 'q', 'i', 'm', 'u', 'c', 'p', '5321', '9477', '4227', '7639', 'p', '1483', '1133', 'z', '2377', '9559', '6071', 't', '8625', '6329', '1827', 'g']

c, d, e, g, i, l, m, p, q, s, t, u, v, z