Your old rating was changed - You have already voted for this item

Hello!
I can't understand why FC displays "Your old rating was changed" for some items when guests press on rating stars:

and why FC displays "You have already voted for this item" for others items...



It should always displays "Your old rating was changed" - but I can't understand how top fix it.
Thanks.

Hello

the ratings is stored into session,
until you close browser window you can revote

about revoting
a user can not vote from same IP (IP1) for same item, until you get a vote from an IP2

Thanks.
It's clear and solved for me.

Hello

in final version v3.3.0,
the registered users they will be able to change vote any time in the future regardless of closing browser window
since their vote will be stored in the "reviews" table ,even if they do not submit a review

about guest voting, you may ask why to keep vote until browser is closed

well, the answer is that we store it in (server-saved) session data,
if we store it in a (browser saved) cookie , then a user may tamper it to say that its previous vote was e.g. 1/5 thus making voting total go even above 100%
so we prefer to allow a revote from the guest user,

probably we should just keep a cookie with ids of items that the guest user voted for, and then just block adding extra votes
at least if user does not clear the cookie then user will not be able to submit more votes ...

Hello
My idea is that guests can change their voice as long as the cookies are saved in the browser. And IP can be different.
Because many users does not have static IP.

Question

how can you trust a guest to store a cookie for something that can manipulate the voting system ?