VAT incl./excl. wrong text display

[Ann]

hello,

I run the prestashop 1.7.2.2 in catalog mode with the theme template lifestyle. The standard situation is: the prices are displayed incl. Tax (with the text: "VAT included")
In case a customer registers with his VAT-ID, via module european VAT number, the prices of the catalog are deducted, which is right. But the text is still "VAT included".
What is to do, that the text is adapting to the content resp. the displayed price. 

I think that the price is displayed by one function while the mention with or without tax is called by another function. It has a functional context, but it is not corresponding.

I do not know why this happens. A documentation is not available.

 

thank you.