Give them more food....
Try using two pots one at either end of the cage even a greedy chip can't be in two places at once.
Mine have enough food to last them about a week stashed away in their aviary among their nest boxes and underground this time of year it is a competition of survival the ones with the most stashed away for winter are the ones that will survive....
Yes I know you may be feeding them every day but they do not understand human logic or thought they only have a driving instinct to survive......
As long as you are giving them plenty of dried food they will pouch it and store it somewhere safe for themselves......
Mind you may also find that they will each dig one another's stash up and move it for themselves..... such is the way of a Chipmunks life
