Couldn't update start and end date based on monthly & yearly selection

jquery
#1

I tried to add start and expire date on monthly & yearly basis for each button. If the monthly is selected, in start date field, current year, date & month should be shown and in the expire date, next month should be shown. If the yearly is selected, in start date field, current year, date & month should be shown and in the expire date, next year should be shown.

The code i have written works only for months. That too in first button only not on every button click. If i change the monthly to yearly, the year is not updating. Please help me to fix this. Thanks in advance.
Please see the fiddle: http://jsfiddle.net/Pkprabu/n3v02f5u/5/