@Apples521 

What was the exact journal entry (JE) made on 12-31-23?  A debit to ??? and a credit to the bank account?

I wouldn't suggest posting this to RE.  That would increase a prior year's net income without ever reporting it as income - your tax preparer will wonder how RE increased.  The answer for the proper entry, IMO, is a debit to A/R and a credit to the debit entry on the 12-31-23 JE, depending on what that is.  If you can provide the 12-31-23 JE, that would be helpful.