DNA: What is the Jagannath 'Ratna Bhandar' controversy?

Today, during the election campaign in Odisha, UP Chief Minister Yogi Adityanath discussed the issue of the key to the Ratna Bhandar of Lord Jagannath. He accused the Naveen Patnaik government of Odisha that the BJD government is committing robbery on God's treasury. The reason for these allegations is the gem store of Jagannath temple, which was last opened in the year 1985. What is the Jagannath 'Ratna Bhandar' controversy?