Bots still attempt to put six axes into their inventory before they cut down trees. But they can only fit one axe! So, the bots get stuck and continue trying to pickup more axes!
But for now I know that you can have the bots pickup an axe, then move, then chop down trees. This will get rid of the bots need to fill their inventory with an item before they can continue.
EDIT: if you make them move and then chop trees, bots will do this (Get axe -> Move -> Chop tree -> Get axe...)
instead of this (Fill inventory with axes -> Chop trees until you can fit more axes -> ...)