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.

['5193', 'h', 'm', '703']
h, m

['r', 's', '2471', 'n', '635', 'k', '3551', '7041', '8765', '1221', '8439', '7773', '6471', 'u', 'p', '2093', '6479', '1435', '6881', 'a', 'y', 'm', 'r', '1627', 'w', 'k', 'b', '3095', '9059', '285', 'y', 'a', 'm', 'x', '637', 'i', '3407', 'e', 'e']
a, b, e, i, k, m, n, p, r, s, u, w, x, y

['n', '1209', '5265', 'f', 'i', '2797', '2003', '1687', 'k', '895', '4441', '6435', '3573', 'w', '577', '1503', '699', '5727', '2059', '1789', '3265', 'l']

f, i, k, l, n, w