Wrong tax payment

Just go through this link, you will get an answer.
https://help.myitreturn.com/hc/en-us/articles/219843707-What-if-I-have-selected-wrong-Assessment-Year-while-paying-tax-#:~:text=Many%20taxpayers%20make%20the%20tax,date%20of%20deposit%20of%20challan

There are 2 scenarios here, one where payment is made offline through bank and second where payment is made online. In the first scenario, if the mistake is discovered within 7 days of making the payment then an application for correction of A.Yr. has to be made to the bank and if found after 7 days the application has to be made to the concerned assessing officer.In the second case, viz. online payment, the application for correction has to be made to the concerned assessing officer only. In both cases, strong followup with the bank/assessing officer is required and also check your Form 26AS from time to time to ensure that the credit is given in the correct A.Yr.