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.

['j', '425', '6223', '6631', 'y', '7649', 'r', 'a', '7933', '7947', 'l', 'l', '8755', 'g', 'b', '3351', '49', 'v', 'm', 'x', '3291', '1007', '1401', 'z', 'q', 'a']
a, b, g, j, l, m, q, r, v, x, y, z

['c', '8389', 'j', '6113', '5843', 'f']
c, f, j

['7161', '4581', '5297', '1577', '9257', 'z', '4959', '9377', 'a', 'n', 'x', 'd', 'l', 'w', 'f', 'j', '257']

a, d, f, j, l, n, w, x, z