I want to block a spam message in iMessage, but I cannot find how to do it?

Hello I am trying to block spam messages in iMessage, and I tried to follow the procedures in:

Block messages in Messages on Mac – Apple Support (AU)

But with this, and my version of iMessage [Version 14.0 (6000)] on my MacOS version [macOS 12.2.1 (21D62) ]

>> I cannot find the menu function to do the following:

1. In the Messages app  on your Mac, select a conversation.
2. Choose Conversations > Block Person, then click Block.

The facility "Block Person, then click Block" does not appear in my MacOS version.

On my iPhone, I have also tried the following:

If you're in Messages, open the conversation, tap the contact at the top of the conversation, then tap the Info button . Tap info  scroll down, then tap Block this Caller.

... but again this function does not appear.

What can I do to block spam messages from unwanted phone numbers????!!