Beds invisibility

I did not play for a long while with Minecraft on my iPad.
When I returned to a world I made in the creative mode, I found out I cannot see the beds anymore.
They are there, the character can go sleep in them, but they are invisible. If I try to erase them the app crashes.
The beds were created before the night/day cycle and the interaction mode with them was available in the creative mode.

Could you help me visualize the beds again?

Viviana