Couple of things:
Any good investor knows that a projection is just that. The exercise is more to help articulate what the investor needs to know is possible: That their infusion of capital can truly accelerate your growth. So it's your responsibility to help create that confidence.

The biggest concern I have for you is that you speak about not knowing what's working. Understanding the mechanics of each channel of spend, and segmenting the users' behavior (churn, upsell, etc) into those channels will give you a much better read into what's really working and IMO, are required before you can really answer the question credibly.

Also, I assume you're doing a Series A or beyond raise, in which case, a potential lead or significant investor asking for projections are entirely reasonable. But if you're raising initial seed and/or this ask is coming from a non potential lead investor, then I'd raise a flag of caution.

Happy to talk through this in more detail if you'd like. Best of luck with the funding round!