make sure there is only one rock and roll object
make sure there is only one rock and roll object

CyrusBiotechnology/pv,CyrusBiotechnology/pv,biasmv/pv,Traksewt/pv,yuhangwang/pv,biasmv/pv,yuhangwang/pv,yuhangwang/pv,Traksewt/pv,CyrusBiotechnology/pv,Traksewt/pv,yuhangwang/pv,biasmv/pv,Traksewt/pv,CyrusBiotechnology/pv,biasmv/pv