If you’ve created bins using Omni’s UI, but you haven’t added a sort on the bin field in the table, then they may not be showing up in order in the visualization.
To fix this, you just need to add a sort in the table by the bin field. To add a sort, simply click on that column’s title in the Table tab to sort it by ascending/descending order. To add a second sort, hold shift + click (see our article on multiple sorts). Once you do this, Omni will order the chart and legend by the order of the bins when you defined them.