Open the Messages app
Open the conversation from the sender you want to block
Tap the contact name or number at the top
Tap Info or Details
Select Block this Caller or Block Contact
Confirm the block
On Android, open the conversation
Tap the three-dot menu
Tap Block number or Block contact
Confirm the block
To block from recent calls or messages, open the number’s details
Choose Block
To unblock later, open blocked contacts in your phone settings
Remove the number from the blocked list