Forgetting whole topics but still getting cards correct

Hello everyone, hope everyone is having a happy new year

I’m relatively new to Anki and have been using it daily for about 8 months now. Recently, I’ve been facing an issue with remembering certain topics over time.

For instance, I might finish studying and fully understand a topic like cardiac arrhythmias (only unsuspend the cards once I’ve reviewed and understood the content thoroughly). However, after a few months, I’ll notice that while I can still answer the cards correctly most of the time (around 90% accuracy), I can no longer have the same deep understanding of the topic as I did during my first pass. If someone asked me to teach the topic to a beginner, I wouldn’t feel as confident as I would have just a few weeks after first learning it… I hope that makes sense

My question is: What’s the best way to handle this issue? After re-learning the topic from my resources, should I:

  1. Reset all the cards for the topic (i.e., start them again as new learning cards), or
  2. Keep the same intervals but use the ‘Again’ button for cards I’m not 100% sure about and ‘Good’ for those I get right, maintaining the current intervals?

Any advice or tips would be much appreciated!