battery range

Hi All, I recently bought a 2021 e300de. Love it so far, but a bit confused by the Electric mpkWh reading from the MercedesMe app. It's telling me (from reset) that it's getting 14.8mpkWh, which would be great if it was true, but I think there's something up somewhere or I just don't fully...

Hello everyone. I have just bought a used Mercedes-Benz c350 e plug-in hybrid. After being fully charged it shows range of 13-14 miles but while using it in the E mode the range quickly reduces and finishes in 4-5 miles or so. Is something wrong with my battery? Or someone else experiencing...