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.

['9425', 'l', 'c', 'n', '5925', '2543', '3935', 'c', '7533', 'j', 'q', '3775', '5897', '9435', '69', 'e']
c, e, j, l, n, q

['2459', '3709', 'f', '8673', '9313', 'm', 'd', 'g', 'c', 'g', 'u', 'f', 'p', 'i', '8771', '3613', '9669', '6221', '1211', '8331', '2295', 'b', 'f', 'm', '1377', '9831', '1751', 'k', '4831', 'm', '2747', '3435', '4543', 'c', '1729', 'e', '7093', '397', 'm', '383', '2019']
b, c, d, e, f, g, i, k, m, p, u

['g', 'n', 'g', 'w', 'n', '2697', '7685', 'v', 'j', 'k', '5511', 'd', '7939', '9885', '4667', '7273', '7477', '7955', '8203', '8229', '8589', '8579', 'h', 'm', 'c', 'l', '2037', 'b', '4265', '8351', '6805', 'h', '7643', 'd', '6953', 'b']

b, c, d, g, h, j, k, l, m, n, v, w