Charge it for 12 to 14 hours with the wall charger.
Low battery/power does strange things.
Computer USB ports may not have enough power to charge (especially, USB Hubs).
Astak does have spare batteries for sale (If you can get the 'Person' who handles the EZReader. I called about 09:30, I am in the same County, and got 'call later'. They have no clue on customer support. That is 12:30 on the East Coast

and no support person?)