Hello @Pei Yoong Ngwee
Welcome to Microsoft Q&A Platform,
CDN endpoints are reserved for sometime once created to prevent other people create the same CDN endpoint right after you delete yours, so i would recommend to try again after some hours.
If the issue remains it could be due to a DNS record removal problem when the CDN endpoint was deleted, if that's the the case please raise a support ticket.
I hope this helps!
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