firmware upgrade B500 is not working ?

usb firmware upgrade on the ep760 to the B500module ware can i find the file for this ?
by app it is not working just for 1 module .


@brilgaming Do you have multiple B500s connected? If you want to upgrade the firmware of each B500, please connect that B500 individually.

Hi everiting is ok now , upgrades ar done on 2 x B500 .

Thnx to the fast support of the bluetti after-sales Engeneer .