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.

Example Input: ['3995', 'n', 'z', '8389', '7857', '3005', 'i', 'e', '1117', 'z', '8251', 'r', 't']
Example Output: e, i, n, r, t, z

Example Input: ['2409', 'q', 'w', 'e', 'x', '4737', 'w']
Example Output: e, q, w, x

Example Input: ['g', 's', 'n', '4451', 'c', 'g', '5847', '3833', 'w', 'v', '1473', '2667', 'u', 'e', 'z', 'c', '3927', 'm']
Example Output:
c, e, g, m, n, s, u, v, w, z