Originally Posted by
Jhieminga
Could it be a spam filter that is moving it instead of your block? Perhaps it has created a more flexible 'rule' based on your block that is also targeting the trusted sender.
I'm not sure whether your spam filter is acting on the BT mailserver or Microsoft office? If it's BT then any fiddling with MS365 won't help.
It might be worth logging into BT directly while MS365 is not connected to see if the message is already in the BT deleted folder.
Spam filters often have "whitelists' as well as blacklists. Adding your trusted sender to a whitelist should ensure that it isn't interpreted as spam.
HTH