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.

['z', '3219', '6399', '2357', '7597', '357', 'k', 'k', 'u', 'd', '6115', 'w', '2921', '8809']
d, k, u, w, z

['1487', '8003', 'd', '7237', 'l', 'y', '2749', 'e', '9685', '2825', 'z', '7743', 'r', '9617', 'w', '4323', '2173', '8419', '2831', '8923', 'l', '2985', '303', 'y', '9409', 'i', 'h', 'e']
d, e, h, i, l, r, w, y, z

['r', 'g', 'u', 'f', '1239', 'j', '9427', '4169', '5453', '7409', 's', 'h', '3975', '9277', 'u', 'a', '5853', '6191', 'o', '549', 'f', 'r', '8063', '2391', '6741', '5845', '6951', 'o', 'k', 'y', '5869', '797', '2615', '7221']

a, f, g, h, j, k, o, r, s, u, y