It is a good start to ask for supports and advice. Just so the community can better support you, please help us understand your business better we can provide specific answers that are relevant and applicable to your business.
Report Martin's answer
More information about your business and what you've done to promote the business so far would be very helpful in getting you the answers you need.
However, generally speaking, a good starting point is understanding why they are not patronizing your business, today? Is it lack of awareness about your business? Do people know about your business, so perhaps it is something else?
If it is lack of awareness, you might consider better understanding how customers learn about laundry companies like yours. Do they use recommendations from friends or family? do they look up listings in directories? do they use internet searches? If so, what terms are they typically searching for? Understanding where people go to learn about laundry companies in your area will allow you to be more focused in any advertising efforts.