Where/How i can get Blueprint ARS IV ??Help

Hello everyone,i don't know where i can get that Blueprint i farmed in lots of places but still no drop i don t have any idea how get this Blueprint i PM SYUS (seller of ARS IV) but he ignored me,he always do this can you guys say me where this drop pls...
Thanks for attention
By: Mariana

Try Juba Waterclock dungeon i drop today Artisan Armor IV

they no longer drop your only hope is to buy 1 that was dropped or sold yrs ago that's how I got mine