This happens sometimes due to the fact that we're processing up to 8 transfers in parallel in order to process the transfers as fast as possible and sometimes, your vote is getting selected for multiple posts in a time-frame of a few seconds.

You can change your votingpower threshold to around 96-97% but keep in mind that the chance is there that if we experience unforeseen issues - your vote might not be cast for 1-2 hours and your votingpower could be stuck at 100% with a high threshold.