I don’t know why I’m not getting a federal tax return because everything’s the way it was last year

Ah, but the tax law has changed. And we're all a year older.  Some deductions/credits (such as the EIC and Child Tax Credit) have age limits.  Look at your 2019 and 2020 returns side by side.  Something may stand out

I was trying to look at 2019 but it doesn’t let me into the whole tax information from last year

It is possible with a change in income you moved into a higher tax bracket.   Therefore, with a slightly higher income your tax liability could also be higher,  Hope this helps.  2021 tax brackets below.

• 37% for incomes over $523,600 ($628,300 for married couples filing jointly)
• 35% for incomes over $209,425 ($418,850 for married couples filing jointly)
• 32% for incomes over $164,925 ($329,850 for married couples filing jointly)
• 24% for incomes over $86,375 ($172,750 for married couples filing jointly)
• 22% for incomes over $40,525 ($81,050 for married couples filing jointly)
• 12% for incomes over $9,950 ($19,900 for married couples filing jointly)
• 10% for incomes up to $9,950 ($19,900 for married couples filing jointly)

IRS has changed the withholding rules to make it less likely you will get a big refund.

If you want a big refund you will have to submit a new W-4 to your employer.