What $303 did you pay twice? Tax due to the IRS or state? Please explain. No one can see your account or your tax returns.
if you paid twice, resulting in overpayment, IRS computers should find a refund for you.
OTHERWISE,
File form 1040-X to report the larger "amount previously paid" in excess.
@kingrogie14
How did you pay each time? Your only proof is your credit card or bank statement showing it coming out. Did you have them take it out of your account but also send in a check?