It's mainly because of 2 reasons :
I don't always have time to draw, unlike before when I have a lot of free time... in the future, I also will close the commission when I buzy, and reopen it again when I have free time. (you can always ask me to do commission, even when I close it. But I won't start drawing before I reopen the commission. Think it as waiting list...)My style is still not steady. It's still change from time to time.. before I find a steady style for the commission, I will close it for now. (really, I feel bad if someone want to do commission because s/he interested with the styles in my gallery, but then end up get a drawing