Why does CaFE show our old bank account on the top of the drop-down box?

If you set one of your bank accounts as Main A/C in CaFE which you use most often in your business, that helps you reduce your operational burden in many ways. 

Go to Master (in the header menu) -> Bank Account -> Click Edit button -> Tick Main A/C and click Save

Please not that you can set only one bank account as Main A/C.

Once you set up your Main A/C, the bank account is always selected as default on the top of the drop down box.

And also, in several screens, you can identify your Main A/C easily as the name of the Main A/C bank account is blue coloured with the font being bold. 

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