Blocked sender emails still in inbox

The problem is not one where a blocked sender uses a slightly different email address. It is a generic problem to all blocked senders. Mail does not send the blocked emails to the bin but puts them in the Junk mailbox where they get mixed up with misidentified non-junk mail and therefore have to be sorted. Mail simply does not do what it says it is doing and is instructed to do. I, and I suspect 1000s of others, simply want mail from blocked senders to go straight to the Bin. It cannot be beyond the wit of the software writers to make something work as advertised.

Probably the sender is using another email ID or a subdomain ID.

For example, if the sender had used mmmm@xyz.com which is blocked by you then the same sender can send you emails using mmmm@abc.xyz.com

Please check the email ID under your list of contacts and the sender's current email ID. Please click this too.

As far as my experience goes this is perpetual.

What I do is, log in to the email account on a web browser and use "Rules" and move all the emails from a domain ID to the bin. Every email accounts have this feature.

Set up rules to filter email in Mail on iCloud.com

• In Mail on iCloud.com, click. ... 
• Click Rules, then click “Add rule.”
• Below “If a message,” use the pop-up menu and text field to specify the type of messages you want to filter.
• Below Then, use the pop-up menus or fields to specify an action for the rule.
• Click Add.

Set up rules to filter email in Mail on iCloud.com - Apple Support

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