WHY IS BURSA PRAYER BEHIND THE CAGE LOCKED?

Bursa Namazgah is one of the two most beautiful prayer places that have survived from the Ottoman period. In recent years it has been restored and opened for public worship. However, in the last period, it was closed to worship again, and it was locked again by surrounding it with cage wires. So who built this prayer room, how has it been used since history, and why is it kept under lock and key today?