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.

[Q]: ['h', 'g', '4563', 'v', 'm', '107']
[A]: g, h, m, v


[Q]: ['7591', '1403']
[A]: -1


[Q]: ['e', 'm']
[A]:
e, m