Do you have to reconfess a sin you committed after confessing it but before being absolved of it?

Let's say someone was going to confession over multiple days and they confessed a sin but then committed it again in the interim. And let's also assume they enumerated it as "numerous" or "countless" times so that there wouldn't have been any difference other than the day they confessed it. Would that be a valid confession or would they have to say it again?