Werkstudent im Customer Service (m/w/d)

Manage all commercial tasks in customer and contract management, including the creation of energy cost statements with price calculation, invoice receipt verification, and advance payment adjustments. Ensure compliance with legal regulations while supporting budget creation and quarterly consumption and cost control analyses. Perform invoice entry and billing for energy and performance accounting. Work as a student assistant in Mittenwald, with the option to work from home or spend 1–2 days in the office. The role supports the company's mission of providing sustainable energy solutions for real estate and industrial sectors, focusing on decarbonization and regenerative energy concepts.