Joseph was forgotten in prison.  He was there because he refused to yield to the sin of adultery.  He was there because a lie was told about Him.  In spite of this, he thrived in prison.  He was used of God even during this time of confinement.  He shows kindness to fellow prisoners, but is forgotten.  God did not forget him there, and God will not forget you there.  When it looks like your life is on hold, your Father has not lost track of you.

“Yet the chief cupbearer did not remember Joseph, but forgot him.” Genesis 40:23 (NASB)