@logger if a watch crashes as often as you describe it, there may be some fault in the hardware. I think contacting support is your best course of actions.
This happens with my vertical when I connect the vertical and the smartphone to a charger with two outputs for charging. It seems that the charger then switches on and off constantly.
@milixov try cleaning the charger and the contacts on the back of the watch, it could be that the watch sees the charger disconnecting and it stops the download.