My lexus rx 350, 2010 can't shift to Park P
 

My lexus can't shift to park P, but before it happens I always find it difficult to shift to P sometimes, I have to shift it twice before it can shift to P, but yesterday it stop can't shift to P anymore but N, D, R, is working well but when I shift to P it keeps showing me that am in R. I have to put my car in N before I can start it. Please anyone got solutions to this? Thank you