Phrases Handling Misunderstandings

I'm not quite following.

B2

Meaning

I don't fully understand.

Example sentences

John: So, the algorithm works by processing the data in parallel.

Alice: I'm not quite following. Could you explain that again?

John: Sure, it essentially divides the task to speed things up.

Alice: Okay, I think I understand now, but... wait, I'm not quite following the last part.