On my 2015 Yaris I got system version XE3864 and I've seen from the bulletin BE-0044T-0415 that there is an update to version XE3934. I put the firmware on a FAT32 USB stick but when I try to do the update, my system doesn't recognise it and nothing happens (jest the insert media message and I can't click Ok). Tried with 2 different USB stick but same result. What do I need to do?