You can't e-file an amended return for Iowa in TurboTax. Refer to the TurboTax article Can I e-file my amended state return?
The reason you're unable to print Form 102 is because it's not finalized for printing yet but will be soon.
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You can check when the forms will be available by using this link.
Yes, please wait to file an amended tax return until your tax return is fully processed, which means you have received your refund or the balance due has posted to your account.
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