Filtering messages from unknown senders turns off iMessage notifications from senders who aren’t in your contacts and sorts the messages into the Unknown Senders tab in the Messages list.
- Go to Settings > Messages.
- Turn on Filter Unknown Senders.
Note: You canʼt open any links in a message from an unknown sender until you add the sender to your contacts or reply to the message.
That might make things less annoying for you otherwise, report spam or junk messages you receive with SMS or MMS, contact your carrier and ask them to take your number off of the telemarketer list and they will do it for you or send you a form to fill out.
Hope this helps!