If i do not apply my state overpayment to my 2022 taxes, where does it go?

[VolvoGirl]

directly to you.   You don't understand.

An overpayment is your refund.   You can have them keep all or part of your refund as an estimated payment towards next year's tax return.  But most people want to get their refund now.   So to get your refund now do not say to apply it to next year.

[ee-ea]

To you as a refund.