from the display interface brief
there is no out traffic on port Xgig 1/0/1 and X gig 1/0/2
when we checked inbound interface we found that all the incoming traffic is coming on slot 0 switch only .
from the ports we can see xgig 0/0/11 to port xgig 0/0/14
when we observe diagram and traffic pattern its found all the traffic input coming on slot 0 means on 1 of the switches only .
in this case this behavior is normal because of feature called local preference , the switch will select the local chassis outgoing interface for sending the traffic
In this case to utilise all port bandwidth , the solution is to disable the local-preference feature so that switch will select the another chassis outbound port also into consideration for forwarding the traffic