You cannot read messages that were blocked by the iPhone’s built-in blocking feature
Blocked texts are not delivered to your Messages app
Check the blocked contact list in Settings > Messages > Blocked Contacts
Unblock the contact if you want to receive future messages
Ask the sender to resend the message from a different number if appropriate
Check other apps the person may have used to contact you, such as email or third-party messaging apps
Review carrier or spam-filtered messages if your carrier offers that feature
Check if the message was sent before the number was blocked
Use a different device only if it shares the same account and message history
Contact your carrier if you suspect messages are being filtered outside the iPhone block feature