This is still happening.
It happened yesterday when leaving a review for our five star sit . I clicked five stars overall and then for each category. When I clicked through to the comment box I saw that the overall category had five stars ( but all white not black ) since I am experienced sitter I knew this wasn’t right and if I pressed submit would show as a zero star sit ! ( The individual categories all had 5 black stars …)
So I went back to the start and repeated the process and same thing again . Now I knew that I had definitely clicked on five stars this time .
So I exited out of the App , logged in and started over - same thing …. Five white stars overall ….
I went away had a cup of tea 
and came back to it a little later …
… this time it all went through correctly…
Definitely a glitch in the system not human error .. and had I not been familiar with how it should look ..I might have pressed submit thinking that the 5 white stars were a five star review ….