Why has my job application disappeared?

I applied for a job on the companies website about 2 weeks ago. The status was updated to "reviewing: hiring manager" 2 days later. However, yesterday I noticed that the job posting as well as my application and the application history just disappeared and I didn't get a response from them. What could be the reason? Why not just send a rejection if they hired someone else?

Why has my job application disappeared?
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