@Martinleayla - you may have a bigger problem: you state the SSN was just issued last month....... (why wasn't it issued when child was born????)
did you file for an extension originally?
what is the date stated on the SS card?????
otherwise, the problem may be that SSNs must be issued prior to the due date of the return (i.e. April 17, 2022 assuming no extension) , there is no tax benefits available. The amendment may be denied on that basis.
From the Form 1040 instructions (page 18)
https://www.irs.gov/pub/irs-pdf/i1040gi.pdf
If you want to claim the child tax credit or the credit for other dependents, you (and your spouse if filing jointly) must have an SSN or ITIN issued on or before the due date of your 2021 return (including extensions).
and while it doesn't state it specfically, to get the Recovery Rebate Credit the dependent must be part of the return and since it would not be (due to a late dated SSN), the IRS wouldn't pay out for this credit either)
Ugh
