Bar Color Change in drill through page

Hi, hoosha_11 

I am glad to help you.

I'm not sure I understand what you mean correctly.
According to your description, you are using Clustered column chart visual, and you have dragged a field to Legend, so the visual shows a different colour, like this?

But you want the colours of the column charts to be blue, even after drill through, like this?

After drill through:

If I understand correctly, you can try to use custom theme colours to achieve what you want:

Then change the colours you need:

I have attached the pbix file for this example below, hope it helps.

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Fen Ling,
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