Learned words count help

I daily use memorise across all my devices. For some reason, my learned word counts show as different depending on the device and version I am using. Anyone have an explanation for this?

Android app - 6,809 learned words,
iOS (ipad) 6,890 words learned,
Windows (Google Chrome) 6,890 words learned,

The points I have are the same across all devices. Why does my Samsung galaxy s8 show a different number of words learned compared to my other devices?

if i quit i will lose all the progress right ?

My problem is

I used to have 1600/1700 words learned only in Russian

Then in Russian 5 Chapter then I could not complete Chapter 16 because of one word. So i reseted the course and I went down to 1200 words. I did the course again but the words remained the same down to 1200.Even if i unignore the words. The count doesn’t go higher.

I quite appreciate you trying to help but your suggestions are basic self-explanatory things that don’t help my word count go up or complete the course. This impacts my motivation especially as I would reach my goal now about 2000 words.