Hello lala134,
It sounds as though you're receiving government or emergency alerts several times within a short period of time. With government and emergency alerts these are alerts sent through your carrier services, and it can lead to contacting your carrier for additional support. Before it leads there you can try restarting your device using the steps in the following article.
Restart your iPhone
If restarting doesn't resolve the issue do confirm that you're running the latest iOS version. You can find the steps for updating in the article below.
Update your iPhone, iPad, or iPod touch
If you continue to have issues after those steps you'll want to reach out to your carrier for additional support as this is a service provided by your carrier.
Have a great day.