Open the Phone app
Go to Recents or Contacts
Tap the number or contact
Select Block this Caller
Confirm the block
Open Settings
Tap Phone
Tap Blocked Contacts
Add the number if needed
Use Do Not Disturb or Focus mode
Enable Silence Unknown Callers
Use your carrier’s call-blocking service
Install a call-blocking app
Report spam calls to your carrier
Unblock numbers from Blocked Contacts if needed