Seems like it's broken. That bing bong doesn't sound good.
I'd accept their offer to replace it. Indeed you lost what you put on it if you don't have another copy. That's one of the basics: always have at least one backup copy (two is better). An another basic: external disks are unreliable, so don't use them as primary storage. But they are nice for using for one of your two backup copies.
Kees
i bought a new hd 1.5tb WD three weeks ago to clean up my computer a week later it was not being recognised (not in my computer) but it was installing and it shows up in device manager and makes same bing bong noise and say's its ready to use but it isn't in my computer.

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