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.

['1345', 'y', '7221', 'h', 'r', '3255', 'k', 'r', 'j', '8639', '467', 'f', 'k', 'n', 'k', 'j', 'l', 'w', '143', 'w', 'q', '5657', '589']
f, h, j, k, l, n, q, r, w, y

['c', '6027', 'o', 'h', 'l', '7893', 'u', 'f', '7661', '4715', '1373', '4799', 'd', 'z', '411', '4753', 'd', '8241', '1589', '4173', '3921', 'j', 'o', '5067', '8879', 'e', 'm', '9543', '9625', '855', 'u', 'd', '5859', '4243', '5747', '5147', '7315', 'd', 'x', 'q', '7841', '7397', 'm']
c, d, e, f, h, j, l, m, o, q, u, x, z

['1473', 'r', 'v', '2747', 'x', 'q', 'e', 'i', 'y', 'c', 'd', 'p', '3495', '2725', 'x', '7791', '135', 'f', 'w', 'b', 'o', 'k', 'n', 'z', '3729']

b, c, d, e, f, i, k, n, o, p, q, r, v, w, x, y, z