I’ve done each of these things and they work great. 1. Go up the chain. Email the head of technology and head of marketing for the company. Tell them that what

I’ve done each of these things and they work great. 1. Go up the chain. Email the head of technology and head of marketing for the company. Tell them that what they are doing is unacceptable. 2. Look up the email service provider. Find their abuse address. Bring it up with them directly. 3. Mark as spam. I give companies one chance to get it right after I unsubscribe. If I keep getting emails I start to mark as spam. If I still get emails I escalate to #1 or #2