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.

['t', 'r', '2959', '2517', 'a', '9959', '729', '511', 'y', 'r', '465', 'c', '687', 'm', 'b', 'm', '3449', '9713', 'g', '8275', '8823', 'a', 'z', 'w', '2185', '6283', '8457', '8137', '7163', '8329']
a, b, c, g, m, r, t, w, y, z

['1189', '7143', '993', '1513', '6449', '9749', '5963', '8159', 't', '3543', 'j', 'i', '4227', '1463', '6431', '4987', 'y', 'q', 'f', '321', 'm', 'r']
f, i, j, m, q, r, t, y

['j', '4675', '3359', '7877', 's', '7115', 'x', '6761', 's', '6145', 'k', '9639', '5771', 'o', 'y', 'k', '2795', '9551', '125', 'n', '4603', '6141', '9013', 'y', '919']

j, k, n, o, s, x, y