Dietitians Act Article 23

The nutrition counseling institution shall issue a receipt declaring the list of service items and the amount of fees charging.The nutrition counseling institution shall not violate the established fee charging or shall desist from over-billing or arbitrarily establishing service items to charge fees.
中文原文 營養師法第23條
營養諮詢機構收取費用,應開給載明收費項目及金額之收據。
營養諮詢機構不得違反其所定之收費標準,超額或擅立收費項目收費。

English translation for reference only; the Chinese text prevails. Not legal advice.