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.

Input: Consider Input: ['f', '9203', 'w', 'f', '3751', '8095', '1319', 'f', '3017', 'r', 'y', '8221', '2715', '9959']

Output: f, r, w, y


Input: Consider Input: ['8829', 'm', '5369', 'q', '5737', '7799', '5705', 'p', 'w', '1983', '4849', 'h', '6771', 'p', 'y', '1071', 'u', '6401', '7723', 'p']

Output: h, m, p, q, u, w, y


Input: Consider Input: ['4589', 'i', '1209', 'w', '81', 'k', 'v', 'j', '9761', 'i', '8187']


Output: i, j, k, v, w