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.

['n', '7337', '6887', '2203', '4663', '2837', '6451', '959', '8027', 'p', 'v', 'q', 'g', '8059', '6151', 'v', '7097', '6583', '7637', '2367', 'w', '9603', '5365', '3773', '1707', 'k', 'x', 's', 'c', 'u', '3641', '6137', '1207', 'k', '5531', '4543']
c, g, k, n, p, q, s, u, v, w, x

['3127', '9253', '5667', '9453']
-1

['4605', '9685', '8877', 'l', 'o', '231', 'a', 'z', 'v', 'y', 'b', 't', '9699', '4213', 'o', '2515', '5197', 'q', 'i']

a, b, i, l, o, q, t, v, y, z