Perhaps former ways of prayer are no longer meaningful for us. When this happens we may think we are doing something wrong. Usually nothing is wrong. Rather, God is inviting us to pray in a different way. Passive prayer may be our call at that time in our lives.
Some people move very smoothly and peacefully into passive prayer while others struggle.
It may be difficult to let go of familiar ways of praying, ways that have nourished us spiritually for years. Though the letting go may be difficult, it may also be God's invitation for us. The story of the elderly woman reciting the rosary on her porch paints a picture of passive prayer. It is one way of praying, one way of praying passively. Perhaps God is inviting you to pray this way.