Merging different emails on Mail APP
Recently, my Mail APP has been randomly merging the sender and subject of 1 email with the body of another email. Very dramatic, because I've erased emails that I really needed to act upon!! The "merged" emails are both from my Yahoo account, but at the Yahoo website directly, they look as they should.
Has anybody else encountered this issue and how to solve it?
MacBook Air, macOS High Sierra (10.13.3)