My Dyson hoover is not picking up, i have cleaned it out no blockages, could it be the brush?

depending on the model turn it over and remove the brush cover plate then remove the brush just lift up and remove the belt you will see once removed a channel where the dirt is sucked up into the collector follow this through the several different parts and clear any blockages then re emble this clears most blockage problems, don't forget also to clean or replace the filters