How to amend a corrected return???

Hi all, I goofed on my original 2021 return and said we had only received 1 stimulus check - the irs corrected my return and gave me a payment due figure rather than the return showing on the original turbo tax return. I then paid the amount due.  I now realise I am a complete idiot and have (slightly) under reported my meagre self employed income so need to amend. I cannot amend my original return as I would have to either re-state non receipt of stimulus check which I'm guessing would constitute a disagreement with the Irs (which I don't want) OR correct it and generate a repayment of a tax refund I didn't receive. EEK.
I'm guessing a phone call to the IRS would be in order, unless someone here has any words of wisdom.

I think a phone call would be best, unless you owe no extra tax since you said the income was “meager “. A correction is not required if the mistake does not affect the taxes. 

https://www.irs.gov/help/ita/should-i-file-an-amended-return