I keep applying to so many different jobs, but nobody is hiring me

I don't get it, I really don't. I've applied to dozens of jobs and not a single one hired me. I know the fault doesn't lie with my resume because I do get calls, and I've had interviews... a lot of them in fact, and none of them ended up giving me a job offer. I literally spend a couple of hours a day practicing interview questions, and I feel like the interviews I've had went well, but nobody is calling me back. Why? What am I doing wrong. I live in Massachusetts, which supposedly has a strong market, yet nothing. I'm starting to run of places to apply to at this point. The thing is, it's no only me, both of my parents (I'm 19) are struggling to get new jobs. What should I do?

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