It's good you have a qualified joint sponsor, but your own affidavit must be accurate as possible. Your 2024 income is not your "current income". Yes, it's the number to enter in the tax section but not the number for current annual income you are using to qualify. My advice is to have a plan for how many pay periods you will be working during the 12 months starting the day you sign your updated I-864, and calculate what that income would be. The only difference in that formula and the standard one is that you will multiply the gross income by a smaller number.
These two obvious mistakes in your first affidavit (current income and not counting your child in the household) indicate to me you failed to study and follow the I-864 instructions. If you didn't follow them, chances are your joint sponsor didn't either. Time to become an A-Student of those instructions, and redo and re-submit both affidavits and their updated supporting documentation.