I had the same thing happen to me. Have been trying to deal with "support" since June 9th.
My board only has 19 miles on it. I turned on the board and the battery percentage on the app was at 94%. Rode for less than 100 feet and the board just STOPPED. Once I got up and got my wind back, the board was OFF. Turned the board back on and got the "battery low" warning. Went inside and plugged it in and in less than 5 minutes received the "Your board is at 100% LET'S RIDE" message.
I Put in a ticket and besides receiving one reply after I called to "send in the diagnostics" it has been radio silence ever since.
I refuse to ride the board until I can get a definitive answer as to what exactly would have caused this and at least some assurance that it will not happen again.