Open the Phone app
Tap the menu or More icon
Go to Settings
Tap Blocked numbers or Block list
Review the list of blocked contacts or numbers
On iPhone, open Settings
Tap Phone
Tap Blocked Contacts
Review the blocked numbers list
On Android, open the Phone app
Tap More
Tap Settings
Tap Blocked numbers
Review the blocked numbers list
Check Messages app settings if needed
Check call blocking settings from your carrier if needed