I decided not to apply my AZ State overpayment to 2025 Taxes. After zeroing out all estimates questions and going back and forth on my state section AND selecting "No" to the question "Apply Overpayment to 2025 Taxes?", my AZ bottom line summary still shows that the full amount is being applied and that my state refund is "$0". Is this a glitch or where I can unselect this? Do I need to delete my AZ file and start all over again?
If you go back through all of the Arizona questions near the end of the State return again, even if you already chose to apply your overpayment to 2025, the question should still come up in case you want to change it. See screenshot below:
If you still don't see it, then yes, you could choose to delete the Arizona return and complete it again.
It happens sometimes, when a taxpayer designates a refund to be applied to the following year, that the entire amount doesn't come over to the next year - either because the IRS made a change to the return, or the IRS or another government agency took part of the refund to pay another debt, or the taxpayer amends the return. It's often safer to cover your estimated taxes either by withholding or quarterly estimated payments.
Please see this help article for more information about applying your refund to next year's taxes.