All you can do now is wait for the IRS notice 6419 to come and then file the 2021 return to get the rest of the CTC you are eligible for ... no more "advance" payments will be sent at this late date.
IRS info:
https://www.irs.gov/newsroom/irs-sending-information-letters-to-recipients-of-advance-child-tax-cred...
A11. Yes. In January 2022, the IRS will send you Letter 6419 to provide the total amount of advance Child Tax Credit payments that were disbursed to you during 2021. Please keep this letter regarding your advance Child Tax Credit payments with your tax records. You may need to refer to this letter when you file your 2021 tax return during the 2022 tax filing season.
For more information regarding this letter and how to reconcile your advance Child Tax Credit payments with your Child Tax Credit on your 2021 return, see Topic H: Reconciling Your Advance Child Tax Credit Payments on Your 2021 Tax Return.
https://www.irs.gov/credits-deductions/2021-child-tax-credit-and-advance-child-tax-credit-payments-t...
A10. Yes. In January 2022, the IRS will send you Letter 6419 to provide the total amount of advance Child Tax Credit payments that were disbursed to you during 2021. Please keep this letter regarding your advance Child Tax Credit payments with your tax records. You may need to refer to this letter when you file your 2021 tax return during the 2022 tax filing season.
This letter will be mailed to your address on file as of the letter’s mailing date. This generally will be the address on your most recent tax return, or as updated through the Child Tax Credit Update Portal (CTC UP) or the United States Postal Service (USPS). For more information regarding CTC UP, see Topic F: Updating Your Child Tax Credit Information During 2021.
https://www.irs.gov/credits-deductions/2021-child-tax-credit-and-advance-child-tax-credit-payments-t...
