In October 2019 we were using QB Pro 2018 and 1000's of our past vendor bills just showed up as "negative" as if they were bill payments. We switched to Enterprise, but no help there. QB's Data Services said they do not have a fix for this error in their software. They said it occurs sometimes when there is not enough RAM. We have 16GB or RAM and only using 5.4GB of it normally. All our past reports are corrupted and Support says to go to a previous Backup that is clean. Has anyone experienced this problem???