Nothing kills a story like revenue. :-(
People want to invest in growth stories - either an abstract (pre-revenue) story about how everyone on earth will perish without your service, or concrete, impressive traction that they can project forward.
But that middle ground where you have proven that people will buy your product but you're sort of limping along with flat revenue is kind of a buzzkill. It's easy for an investor to visualize in the abstract going from $0 to $100M ... it's very difficult to visualize $0.1M to $100M.
Sooooooo, you have two choices:
(1) Manufacture traction with some bullshit metrics. There's *nothing* wrong with this. Find something that can be extrapolated into future growth. Maybe 10 of your customers took forever to close and have low growth potential... but maybe 1 customer has some unique characteristics where they bought instantly, are planning on rolling it out to 50 divisions. Convince an investor that there are 10,000 of these companies on the planet and you need money to double down and focus product and sales on this segment, then maybe they don't care so much about current slow revenue growth.
(2) Go back to story-telling mode. Just pretend you're a pre-revenue company and tell a story that is much larger than your existing product. Your existing product is simply to prove out a few concepts, but the real opportunity is to do X. They may even be impressed that you're dismissing real revenue as insignificant compared to the big idea.
Everyone here knows how hard it is to build a product and get 10-15 paying customers. You're to be congratulated for that. But remember that the investor is being hit with 5 pitches a day, promising him the world. You need to start promising the world in a way that isn't inconsistent with your existing revenue.