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', '491', 'x', 'u', 'z', 'q', '5411', '7629', '8261', '8629', '1441', '5139', 's', 'm', '6463', 'u', 'z']
Example Output: m, q, s, u, w, x, z

Example Input: ['749', 'r', 'a', 's', 't', '5905', 'm', 'd', '8437', '4583']
Example Output: a, d, m, r, s, t

Example Input: ['t', '1949', 'y', '5873', 'r', '2189', '8669', 'm', 'x', '1753', '627', 'n', '7051', 't', '6957', 'l', '7757', '9267', 'm', '9803', '6081', 't', '3291', 'o', '7043', 'k', '4287', '3275', '9025', 'w', 'y', '8667', '1819', '3107', '8865', 'n', 'i', '5273', '6301', 'n']
Example Output:
i, k, l, m, n, o, r, t, w, x, y