My iPhone 13 pro is unable to record instagram story by using volume button

Hello and welcome to Apple Support Communities, Foxfoxfox18!

We understand you're trying to record a video from the Instagram app using the volume button to start the recording. We'd be happy to provide information to help you out.

Does the volume button work correctly when recording a video using the Camera app? You can find the steps on how to do that in this article: Record videos with your iPhone camera.

If the issue is only happening when using the Instagram app, you'll need to reach out to the app developer to report the issue and receive assistance: How to contact an app developer

Have a great day!