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: ['r', 's', '3409', 'a', 'e', '6855', 'i', 'n', '8655', 's', 't', '8401', 'u', '9603', '8815', 'q', 'a', 'x', 'i', '8455', 'e', '5877', '3917', 'p']
Example Output: a, e, i, n, p, q, r, s, t, u, x

Example Input: ['6411', 'x', 'i', '267', 'z', 'e', '5483', '8033', '3697', 'z', '4167', 'e', 'f', '7229', 'i', 't', '2197', 'g']
Example Output: e, f, g, i, t, x, z

Example Input: ['1811', 'f', '6071', '8507', '21', '7595', 'l', 'q', 'g', 'g', 'q', '7251', 'x', 'r', 'x', 'r', '8945', '2949', '7571', 'v', '6399']
Example Output:
f, g, l, q, r, v, x