The concept of voting too often, especially when a translator requests proofreading, is preposterous. I have voted twice (maybe thrice?) in the last 10 minutes, and the second (or third?) vote was rejected because I supposedly vote too often? O sorry, I will try to refrain from proofreading translations in the future!
No, but seriously: this cannot be the purpose of the rating system, to vote only once in a blue moon. If there is voting function, I damn well want to be able to use it.
If lyricstranslate.com does not want its users to use the rating system, then it should disable it, and in its stead put an alternative (other than just commenting) to proofread translations.