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.

['5181', '8651', '963', '2111', 'g', '7913', '8335', 'o', '1387', '9225', '6517', 's', 'r', '2291', '3699', 'y', 'y', '4223', 'i', '9109', 'm', 's', '8585', 'l']
g, i, l, m, o, r, s, y

['m', '6537', '4063', '6413', 'k', 'd', '2479', 'p', '2251', 'q', '7079', 'r', 'd', 'p', '3347', '1391', '9847', '4487', 'u', '6951', '5285', '5837', '6747', 'r', 's', 'c', 'x', 'b', 'q', 'y', 'd', '331', '679', 'v', '1919', 'f', 'p', '1267', '3151']
b, c, d, f, k, m, p, q, r, s, u, v, x, y

['4477', '2663', '2207', '4015', '69', '2319']

-1