i have a GC storage bucket. I want to point a subdomain to it. lets say my storage bucket url is my-bucket.storage.googleapis.com.
It servers some files under it my-bucket.storage.googleapis.com/files/notes.txt.
i want to have the same file with my sub domain storage.example.com/files/notes.txt.

P.s
I tried adding cname record in my DNS but its not helping.
it returned this response

<Error>
<Code>NoSuchBucket</Code>
<Message>The specified bucket does not exist.</Message>
</Error>

Also there is already a question answered but this solution is not applicable in my case as i cant change the name of my storage bucket, nor can i create a new one, its already in production and other mutlple services are actively using it.