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.

['7123', 'm', 'h', '4065', 'c', 'n', '187', '3899', 'r', 'k', '2071', '9481', '6277']
c, h, k, m, n, r

['3035', 'f', 'k', 'e', '3023', 'p', '9667', '5277', '4757', '8433', 'g', '1399', '7721', 'n', 'p', '7469', '7581', '5679', 'g', 'q']
e, f, g, k, n, p, q

['1409', '4645', '7831', '8831', '7275', '6469', 'j', '9253', 'w', 'b', 'f', '6819', '8445', 'z', '3329', 'h', 'l']

b, f, h, j, l, w, z