battery glitch

Don't worry about the slight mismatch. I've seen macOS report slight differences when using the GUI interface or a built-in macOS command line utility to report these values. Plus batteries use chemical reactions which can cause things to change. I've removed a charger and saw the battery charge level increase. Some of it may be due to how the electrical circuit is wired and some of may have to do with the unpredictable chemical reactions within the battery. Don't worry about the small deviations or it will drive you crazy.