My only suggestion would likely that the bubble the person is blowing is too transparent, maybe make it more obvious?
the person doesn’t look like he’s blowing bubble
the lighting is bad.
it doesn’t really look like they are holding pets.
the posing is bad (make it r15 and every body part bended).
so… its a 3/10!
I suggest using blender.
good day sir
Alright thanks for the feedback! I tried putting a bit of reflection on it so should I have that or no?
I mean from your GFX, the name of the game is BGS, but since the center of the thumbnail are people trading pets, users looking at it will think that it is a pet trading simulator, when it is not at all. You can have the person blowing the bubble into holding a pet, and the two people in the center to blowing bubbles, that would probably help define your game more, and by less transparent, I mean make the color of the bubble a little darker so it is easier to see. 
The characters are stiff, use R15 and use bending limbs and stuff. The lighting is very bland. The angle of the picture is pretty weird.