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: ['1449', 'a', '6261', '303', '4651', 'n', 'u', '1595']
Example Output: a, n, u

Example Input: ['4925', '9943', '7935', '4387', '2449', '5797', 'i', '1517', 'w', 'e', '9525', 'y', 't', 'e', '2793', 'v', '9897', '8709', '7247', 'o', 'f', '5549', 'q']
Example Output: e, f, i, o, q, t, v, w, y

Example Input: ['w', 'v', 's', '9001', '8329', '9207', '8531', 'h', 'l', 'w', 'o', '2227', '6573', 'q', '5039', '4757', 'k', '3121', 'e', 'f']
Example Output:
e, f, h, k, l, o, q, s, v, w