Apple care claim

If you have iOS 12.3 go to settings/general/about and it will tell you your warranty status.

If you haven't updated yet use this link-->Check Your Service and Support Coverage - Apple Support

And if you no longer have warranty coverage here is the information on repairs-->iPhone Repair - Official Apple Support

If your iPod Touch, iPhone, iPad or iWatch is Broken

Apple does not usually fix iDevices except for screens – iPhone Screen Repair & Replacement - Official Apple Support – and minor work they can do in their shop. Instead, they exchange yours for a refurbished or new replacement depending on the age of your device and refurbished inventories. On rare occasions when there are no longer refurbished units for your older model, they may replace it with the next newer model. You may take your device to an Apple retailer for help or you may call Customer Service and arrange to send your device to Apple: You can make an appointment at the Apple Retail Store - Genius Bar and take it in for service. You can also look for an Apple Store - Find a Store - Apple. You will find respective repair costs from the appropriate link:

• iPod Service Support and Costs.
• iPhone Service Support and Costs.
• iPad Repair - Official Apple Support
• Apple Watch Service Answer Center.

Apple - Support - AppleCare

How to manage your AppleCare plan

Check Your Service and Support Coverage - Apple Support