/fill command isn't taking the inputs correctly

The /fill command isn't taking the inputs inputs correctly, when i use the command like /fill 5 63 10 10 70 20 air, for some reason it starts to take input of the "to" cordinates, before completion of the "from" cordinates. That means while I'm still typing the "from: xyz" 5 63 10, it's taking the 0 of the 10 as the x cordinate of the "to" function. Due to this I'm getting an error which says "Can't place blocks outside of the world".