Hi davewhunt,
Welcome to the Apple Community.
Phone numbers that you manually block appear under Blocked Contacts.
Apple Support have an article online that may help:
Block phone numbers, contacts, and emails on your iPhone, iPad, or iPod touch
For iMessage:
Go to Settings > Messages.
Under SMS/MMS, tap Blocked Contacts.
Complete article: https://support.apple.com/en-us/HT201229
Or
You may have used "Silence Unknown Callers" or a third-party app to block spam calls on your iPhone.
This blocks phone numbers that you've never been in contact with and don’t have saved in your contacts list.
(Settings > Phone, then scroll down, tap Silence Unknown Callers and turn on / off the feature. )
Complete article: https://support.apple.com/en-au/HT207099
Hope this helps you :-)