GALAXY S7, Cant change lockscreen wallpaper

im always changing my wallpapers on my phone, but since yesterday, i cant change the lockscreen wallpaper, it always follow the home screen no matter what i try, even when i look up lockscreen and home wallpaper option, it shows the wallpaper i chose, but when i lock and unlock my phone, lockscreen keeps the same as home screen,
i did several reboot, change themes, reset to default, even when i only change the home scrn the lock scrn follows, nothing works, im resourceless...help me please.