Hi, it is quite hard to help without more details. I think that if you could post the source of your process somewhere somebody will definitely help you. Please, could you post the source of your process somewhere? And second question, what version of JBoss BPM Suite do you use?
As Jozef said it's quite vague.
Anyway the message says that you haven't defined a process pariable "ringPrice" that you are trying to use somewhere.