After running the suggested RadPower debugging steps I resolved that it might be the battery controller.
Email responses were slow.
One response suggested online chat might be a way to go.

Here is a suggested link.

The team is available Monday through Friday from 9 am to 3pm Pacific Time. We have found the most efficient way to help customers is via our Live Chat team. You can contact our team via Live Chat at the bottom right of any of our help center pages.

I am having the same issue with what I call a long wait for support.  The telephone support number is down I have been waiting for 3 days for a response to my message request

My motor Rad Pro 6 suddenly stopped and it will not power up.

I have less than 100 kilometers on it and it did not get wet.

The connectors look good.

If I remove the battery and reinsert it  the remote and display powers up without pressing the on/off switch.  If I activate the throttle the motor does not run.

If I power the bike off with the switch it will not power up again with the switch.