Hey there DD526,
If you’ve already followed all the steps in Block phone numbers, contacts, and emails on your iPhone or iPad, and the sender’s emails are still appearing in your inbox, make sure you’ve got the latest iOS update installed. That can sometimes resolve issues like the one you’re describing. Here’s how to update:
1. Back up your device using iCloud or your computer.
2. Plug your device into power and connect to the internet with Wi-Fi.
3. Go to Settings > General, then tap Software Update.
4. If you see more than one software update option available, choose the one that you want to install.
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6. Tap Install Now. If you see Download and Install instead, tap it to download the update, enter your passcode, then tap Install Now.
Read more here:
Update your iPhone or iPad
Also, what account is the mail coming to? If it’s iCloud, you may be able to have the email go to junk automatically following the steps here:
Report and reduce spam in iCloud Mail
If it's a different account like Gmail or Yahoo, you can reach out to them to see if they have any way to block the sender as well.
We hope this helps. Take care.