Glitch?

I am at the point where I have defeated the chimera boss in the Deist Cavern room, and I am supposed to put the Wyvern Egg in the spring the beast was guarding.

But it WONT LET ME DO THIS. The item is grayed out, even when I am standing next to the stream!

Playing this on an iPad Pro.

Hoping this can be fixed? Please?

johnnynod about FINAL FANTASY II, v1.1.1