Have you done a parasite cleanse? If you rad in Hulda's books, she states that if a Liver Flush is unproductive, that parasites may be blocking the bile ducts so the stones and chaff can't be flushed out. She recommends doing a parasite cleanse and kidney cleanse before starting liver flushes.
Not everyone needs these preliminary cleanses; however, if a liver cleanse (especially 5 flushes) is/are non-productive, then you need to seriously consider doing a parasite kill/cleanse.