Greetings keisy208,
Welcome to Apple Support Communities. Try these steps to help with this Siri trouble you're having:
Set up Siri to recognize your voice
1. Go to Settings.
2. Tap Siri & Search.
3. Turn off Listen for "Hey Siri," then turn it back on.
4. When the Set Up "Hey Siri" screen appears, tap Continue.
5. Say each command that you see on your screen.
6. Tap Done.
If Siri stops responding
1. Go to Settings.
2. Tap Siri & Search.
3. Tap Siri Responses.
4. Tap Prefer Spoken Responses to hear Siri speak responses, even when Silent mode is turned on.
Further troubleshooting steps can be found in the Apple Support article:
If "Hey Siri" isn't working on your iPhone - Apple Support
Should this issue persist, get in touch with Apple Support for further assistance:
Get Support
We hope this helps you.