The handwriting tool in my messages is not working

Hi palak243,

Thanks for coming to Apple Support Communities for help today.

Let's double-check the steps you are following to create a handwritten message: Use message effects with iMessage on your iPhone, iPad, and iPod touch

"Send a handwritten message

You can personalize your messages by adding a note in your own handwriting. Your friends and family will see the message animate, as if it were being written in front of them. To send a handwritten note, follow these steps:

1. Open Messages and tap the Compose button  to start a new message. Or go to an existing conversation.
2. If you have an iPhone, turn it sideways and tap  on the keyboard. On an iPad, there's no need to turn it sideways, just tap on the keyboard.
3. Write your message or select one of the options at the bottom of the screen.
4. If you need to start over, tap Undo or Clear. When you're finished, tap Done. Then tap the Send button ."

If you continue to have an issue with it, try restarting and be sure to have updated to iOS 15.4.1: Update your iPhone, iPad, or iPod touch.

Then if it still isn't working, let us know exact details regarding what happens when you attempt to use the feature.

Have a fantastic day!