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.

['7799', '8163', '3389', 'x', 'k', 'm', '6085', 'f', '1131']
f, k, m, x

['5337', '4877', '9443', '3445', 'u', '2571', 't', 'n', 'x', '1985', '5145', '3397', 'p', '9259', 's', 'x', 'u', 'c', 'g', 't', 'j', '829', '8273', 'e', 'j', 'r', 'x', '865', '4773', 'h', '4407', '8591']
c, e, g, h, j, n, p, r, s, t, u, x

['1347', '211', 'h']

h