Last month I worked with another forum user in the same situation. I tried for a long time to explain this. I don't think he was attentively reading my replies.
My recommendation was to file prior year amended returns on paper, hand written using IRS.gov fillable PDF forms.
E-file of 2023 1040-X is still available.
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How to make TurboTax do it is a completely separate topic.
Based on other forum posts, good results using TurboTax to amend is sporadic at best.
(of course, those who have no problem, do not post on the forum).
@msv1
