So in the past you would have to change your login password everytime you wanted to reload your account (well if it had been more than 30 days).
This was bothersome though manageable because you had to keep track of your new password all the time.
Then, about 6-9 months ago they added an additional restriction where you had to provide your secret password in order to change your login password. Well, if you lost your secret password, or weren't paying attention to it when they sent it to you, you were SOL.
Now it seems that you can recharge your account without changing your login password. This makes having the secret password not so important anymore.
If you need to recover your secret password, you can either send an email, or call customer support. It took me some digging and I needed the help of a Taiwanese friend during my last trip there to figure it out, but it is in the support pages at wowtaiwan.com.tw somwhere.
Once you get the correct contact, you need to have the following information in order to get the secret password sent or released:
1. Passport/ID information (this is the ID you typed in during your initial registration. The profile data is partially obscured, so you need to know what you originally entered).
4. maybe some of the region and contact info, but that is all listed on your profile page.
If you have a friend call in for you (as I did due to language issues) make sure they say that they are you, otherwise customer service is not allowed to help.
Good luck recovering your secret password...