I'm Ava from Shopify Support, I'd like to help here.
Shopify uses the Sender Policy Framework (SPF) to verify your customer email address for the automatic notification emails that your customers receive. These include order confirmations + shipping confirmation/updates! This SPF prevents notification emails from being flagged as spam, removes the via Shopify note from the sender information, and displays your customer email address instead of email@example.com in the sender field.
To prevent your emails from bouncing, you can add SPF Records to your domain's DNS settings! If you have bought your domain from Shopify, can you try adding the SPF Records to the Shopify domain from within the admin?
1. From the admin, go to Online Store > Domains
2. Click on 'Manage' beside your primary domain
3. Next click on 'DNS Settings' at the top of the page
4. Here you can add the record! Click on 'add custom record' and select TXT Record
5. Add @ in the Name, and v=spf1 include:shops.shopify.com ~all in the record
6. Save changes!
I have made a video here on how to do this.
If you have bought your domain from a third-party host (like GoDaddy) and not from Shopify, there is a more general guide here:
Log in to your domain hosting account.
Find your domain's TXT record. This usually appears beside the CNAME record and MX record.
Add the following SPF record to your TXT record: v=spf1 include:shops.shopify.com ~all
Save your changes.
This can take a couple of hours to propagate; usually 24 hours for any domain changes, but it can often be faster! I would recommend waiting a little while, then sending a test email to yourself to ensure all emails are being delivered.
Let me know if that works for you! If you are still seeing errors, or the email is not showing up in your inbox/spam folder, let me know here and I can continue to look into this for you.
Social Care | help.shopify.com