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.

Example Input: ['1985', '729', '169', '1299', 'l', 'z', '6809', '3083', 'w', 'f', '1989', 'z', '889', 'x', 'r', '1601']
Example Output: f, l, r, w, x, z

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

Example Input: ['v', '4255']
Example Output:
v