Re-ordering bars in a bar chart or a box plot on x-axis

I’ve been trying to work this out for a while - how do I re-order bars on the x-axis on a box plot or bar chart? As an example, I have months of the year - if I use numbers (1,2,3 etc.) then it looks fine but if I use the actual month’s name, it orders them starting from April. Any clue how to solve that?