HTC One M8 Encrypted Password Change?

[AC Question]

Hi,

I have a HTC One M8 and I have Encrypted my password for my internal storage and my external storage (SD CARD) my only problem is, I found that the password I provided in the beginning is too simple.

I want to make it harder by adding symbols and numbers in to this password, is there a possible way to change my password?

Thank you.