Interview Canceled and I’m worried

I had a phone interview scheduled for today at a non-specific time. Just early afternoon through to the evening. This is with a big company and kind of my dream job. I cleared my whole day and stayed home to be ready for this. As the afternoon progressed I decided to email the hiring manager to be sure they got my confirmation for the interview.

He told me that yes he got it but is canceling the interview because they are too busy and is going to check their schedule and get back in touch. Is this something that I should be worried about? They didn’t say they filled the position but I’m honestly not expecting them to reach out again. Is this common for companies to do? Am I right in my concerns?

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