I have a new Helkama CE8 (made in Finland) e-bike with a shimano steps E6100. I am getting frequent E20 errors or sometimes just a blank screen. I have had it back to the dealer and they replaced a cable between the battery and the motor but it did not solve the problem. I can usually temporarily fix it by removing the battery and replacing it, but it doesn't last for long. Have any of you had similar problems with the shimano steps and how did you solve it?

I would check around the battery connection. Rack or contact points. The mounting point may have gotten loose.

Update. The bike shop took the bike back and exchanged it for an upgraded bike. :-) I'm thrilled with the new one!