Girls, has anyone encountered this or can you just advise?

Girls, has anyone encountered this or can you just advise? My daughter sleeps in a cocoon that lies in her crib from birth Now it's lagging behind us a little bit, but we can't remove it As soon as I put her asleep in the crib she searches for it with her hand And if she doesn't find it, she wakes up It's not working What should I do What can I replace it with