You're refactoring a React application to use Immutable.js. After the changes, you notice the components aren't re-rendering as expected. What could be a likely reason?

Immutable.js objects are shallowly compared by default, meaning that it may not trigger re-renders when you expect. To solve this, you should ensure that you use Immutable.js functions like set or merge when updating your state to create new objects with updated values. This will ensure that React recognizes the changes and re-renders the components appropriately.