Here are some ideas, I’m afraid this will be generic without knowing more about the business.

• You said you pitched everyone in your niche industry. Are you actively nurturing that audience, repitching, and staying top of mind? What works well in sales and marketing are constantly changing so are you experimenting with new channels or ways to engage with your buyers?
• Are there new products or services you can bundle or upsell to your current customers?
• Consider your bottom line too, are there areas you can improve efficiency or automate to get better profit margin?