Essays and reports differ in terms of layout and focus
Essays traditionally, don’t have headings; instead writers develop and sustain an extended argument throughout the text, moving from logically connected paragraphs to create a text that makes sense to the reader. Nowadays it is fairly common for students to use headings and sub-headings in essays if it makes sense to do so. However, your lecturer may have a layout preference for essays without headings, so if you're not sure check with your lecturer or module handbook.
Reports are divided into sections with headings and sub-headings so that the reader can find specific information easily. Business reports often present information visually using graphs, tables and diagrams. Your module handbook will often give you a structure to follow.
An essay tends to focus on concepts, issues and/or theory. The focus of a report is more concrete: the report looks at an issue in a real-world context. Essays, especially business essays, often use real-world examples to illustrate a concept or theory but a conceptual, or abstract, idea is the focus. Business reports often focus on a case study organisation and draw on relevant literature to understand the company.