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: ['w', '6291', '3939', '9569', 'u', '1635', '3359', '8335', 'n', '2799', '7359', 'k', 'm', '2817']
Example Output: k, m, n, u, w

Example Input: ['h', 'g', '4563', 'v', 'm', '107']
Example Output: g, h, m, v

Example Input: ['4743', '3547', '1547', '365', 'k', '3177', '6221', '8695', 'g', 'r', 'j', '5873', 'c', '1921', 'v', 'w', 'd', '2861', 'a', 't', 'r', 'u', 'a', 'c', '8315', '9439', '2083', 't', 'i', '5477', 'h', 'k', '2565', '1639', 't', '7841', 'b', '5623', 'e', 's']
Example Output:
a, b, c, d, e, g, h, i, j, k, r, s, t, u, v, w