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: ['6143', 'y', '5505', '9813', 'r', 'v', 'u', '8681', '2387', 'u', 'o', 'm', '9793', 'm']
Example Output: m, o, r, u, v, y

Example Input: ['1121', 'j', '1433', 'g', 'l', '1479', '1699', 'j', 'a', '8507', 'd', 'a', '5229', 'k', 'x', '4549', 'e', 'p', '1367', 'u', 'd', '785', '215', 'e', 'f', 'a', '101', '7575', '7965', 'p', 'i', '5637', '1005', 'i', 'y', '181', 'r']
Example Output: a, d, e, f, g, i, j, k, l, p, r, u, x, y

Example Input: ['y', '4995', 'o', 't', 'y', '9023', '3301', 'r', 'z', '7531', '3379', '5979', '5553', '7267', '3493', '5775', 'o']
Example Output:
o, r, t, y, z