What is the best practice when it comes to case resolution where multiple follow-ups are required from you to your customer?

In my case, we have follow-ups with our patients and we document everything as a case. Would it be best practice to resolve the case after the 1st follow-up and create additional cases for the 2nd & 3rd follow-ups?

If we keep the case open for a month, that will affect our case resolution KPI and maybe others.