Why do my Chinchillia's have issues?

i have 2 one year old male chin's (Skittles and Gizmo) that my wife and i love very much. Skittles used to ok with us picking him up and bringing him around the house, but now he will not allow us to pick him up and his stool size has change to about half what it used to be. they both do not seem to want to play with us, but they get to play for about 1-2 hours every other day. i am concerned about the changes Skittles has made and that they both do not seem interested/scared of us. i've tried several different methods for trying to connect with them, but nothing changes.