So you are missing around 1400? That could be the 3rd Stimulus payment. Did you get it back in March - May or later? Check you bank statements. You might have tried to claim it again on your tax return line 30.
You should have got IRS letter 6475. Double check your bank account and your IRS account
Your Online Account | Internal Revenue Service
If the IRS thinks they sent it to you but you didn't get it request a trace for a missing third Stimulus payment
https://www.irs.gov/newsroom/questions-and-answers-about-the-third-economic-impact-payment-topic-j-p...
