why won't my cruzer play in a car stereo after i attempted to use it for a

As far as I know ALL car stereos need the flash drive or memory card (w/card reader) inserted into the USB port to be formatted as FAT32 in order for them to be able to read it. Therre may be some brand-new vehicles that will accept and read the newer larger drives formatted as exFAT but I haven’t heard of them yet.