You shouldn't have any code which is referring to "org.bouncycastle" as a type, because it isn't one. So check the line which that error message referred to and fix it.
For a better answer, post a better question. A better question would include the code, the complete error message (copied and pasted), and something about which line of code the error message was about.
Gravity is a harsh mistress. But this tiny ad is pretty easy to deal with: