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.

['t', 'h', '6141', 'g', 'f', 'z', 'n', 'b', 'k', '9059', 'y', 'p', '4289', '2683', 'a', '3267', 'w', 'p', 't', '3623', '7759', 'a', 'o', 'm', '9815', 'q', 'u', '8051', '6871']
a, b, f, g, h, k, m, n, o, p, q, t, u, w, y, z

['1983', '1835', '6543', '6399', '4177', '9385', '7127', 'p', 'l', 'u', 'g', 't', '3423', 'g', 'b', 'l', '3133', '2429']
b, g, l, p, t, u

['q', 'm', '7037', '8537', '2995', '2839', 'v', '5199', 'v', '4209', '3449', '977', '1893', '7017', '645', '1485', 'h']

h, m, q, v