hi,
have one.
if its on batteries make sure they are new and if they are check battery terminals use an emery board or sandpaper to clean the battery terminals or you have to use the exact right power supply also with at least an 1 amp output. use the right power supply.
e is for movement while in operation touch start and should clear the following link is owner operator manual https://bs.fcdn.nl/data/staticmedia/eigenschappen/82601/1375/R3[1].pdf