After you file

An extension for what tax year?  There is no such thing as an "extension acceptance letter or acknowledgement code" --- so what are you trying to do?   

 

If you had an extension for 2022----

 

https://ttlc.intuit.com/questions/2879424-how-do-i-print-my-4868-extension-form-after-e-filing-it-th...

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