Официальный веб-сайт башни. Статья о том, в каких местах удобно
делать удачные фоточки ея. Также пояснение насчёт запрета: https://www.toureiffel.paris/en/news/recreation/best-spots-photographing-eiffel-tower
https://www.toureiffel.paris/en/news/history-and-culture/15-essential-things-know-about-eiffel-tower
There is nothing that says you can't take photos of the Eiffel Tower at night. Private individuals are free to take pictures of the Eiffel Tower at night for private use or to share on social networks, for example.
The situation is different for professionals: the Eiffel Tower's various illuminations (golden, sparkles, beacon, and illuminations for special events) are protected by copyright. Any nighttime pictures of the Eiffel Tower used by professionals for professional ends thus require previous authorization from SETE (Société d’Exploitation de la tour Eiffel - the Eiffel Tower management firm) and eventually the payment of usage rights.