Changed tax rate from 16% to 19% but still using 16%

Hi there,

from today in germany the tax rate must be 19% again. The last change in June by decreasing the tax to 16% was made by an external developer. I can’t get him now anymore and don’t know what exactly have changed. It looks like he changed the original calculation method, because I changed each standard rates to 19.0000 in woocommerce settings, but no effect. I also can’t find any code in functions.php regarding taxes.
The external developer wasn’t so experienced. Can anyone tell me where I can find the code of tax calculation?

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