POSSIBLE BUG: tax calculation not correct

Hi, we are using you plugin…great plugin but we think it has an error when it has to calculate the fee…with tax…

if you see here we would the plugin calculate 6% fee + 21% VAT on 200€ (vat included)… but the plugin calculate a 13,96€ fee when, following out logic (probably incorrect)…we were waiting for a 14,52€= (200*0,06)*1,21 …. where we are wrong?

Thank you very much
Angelo