$5600 different? Did you already get the 3rd Stimulus payment? You get 1400 for each person. Are you married and 2 dependents?
Check if there is 5600 on 1040 line 30. The IRS shows they already sent it to you. But you tried to claim it again.
Double check your bank statements and Check your IRS account (both accounts if married)
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...
