Understanding % Conversion Rate Differences: Uniques vs. Totals

Hi guys! 👋 Looking for help in understanding % Conversion Rate differences between "Uniques" and "Totals". Here's my problem. I am monitoring the step conversions between the most important steps of our app funnel (rental car comparison & booking app). This funnel has the following steps:

P.S. Users need to do all these steps to be able to submit a booking. So what I am looking at apart from the overall CVR (step 1-6), are all Micro Conversion Rates (e.g. step 1-2, step 2-3 etc.). When I compare the values for "% Conversion Rate (Unique)" and "% Conversion Rate (Totals)" that Mixpanel gives me for most of my Micro Conversion Rates, they all look relatively the same, with the "% Conversion Rate (Totals)" being slightly higher than the "% Conversion Rate (Uniques)". This is NOT the case for my last funnel step (Step 5-6; Summary --> Submit). Here, for reasons that I do not understand, my "% Conversion Rate (Uniques)" remains stable, but "% Conversion Rate (Totals)" drops since late August. And as I am struggling to understand the exact difference between "% Conversion Rate (Uniques)" and "% Conversion Rate (Totals)", I am similarly struggling to find an explanation for my phenomenon. Hoping to reach someone who can shed some light on that issue and help me understand what might be going on. For any potential Berliners here, happy to buy you a coffee haha ☕ ✨ Cheers, Chris 🤓