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.
Q: ['5693', '8401', '2577', 'r', 'n', '8671', '8827', '4215', 'k', '8689', 'i', '2877', 'v', 'h', 'r', 'y', 'm', '2793', '4603', '2367', 'i']
A: 
h, i, k, m, n, r, v, y