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.

['1447', 'q', '9529', '2971', 's', '7351', '6753', '3493', 'v', 'c', 'x', '3097', '9145', 'b', 'e', 'b', '2967', '6933', 'e', 's', 'v', 'f', 'z', 'r']
b, c, e, f, q, r, s, v, x, z

['895', '2049', '8839', '1773', 'v', '467']
v

['9657', 'm', 'p', '7377', '1109', 'z', '6853', '1143', 's', 'z', 'v', '369', 'q', 'b', '5591', '7983', 'n', '1001', '9299', 'q', '2831', '7857', '5631', 'y', '2285', 'k', 'r', '1763']

b, k, m, n, p, q, r, s, v, y, z