Hi @Jason P,
Thank you for your reaching out and welcome to Microsoft Q&A!
It sounds like there are still a few records in there. You can check for SRV records using NS lookup:
How to verify that SRV DNS records have been created for a domain controller
Also under the zone properties, make sure it is removed from the Name Servers tab.
I hope this helps! If you have any more issues or need further assistance, feel free to share with us!
Best regards,
Lucy Chen
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