If the company is not providing an increment letter, you can still demonstrate your salary increment through other means. One way is to maintain a record of your salary changes, such as pay stubs or direct deposit records, to show the progression of your salary over time. Additionally, you can request a formal confirmation of your salary increment from your HR department or supervisor via email or written documentation. This will serve as proof of your increased salary even without a specific increment letter. If needed, you can also discuss the issue with HR to explore alternative ways to document and acknowledge your salary increment.