As an intelligent and well educated person, who´s Linkedin profile probably appears as blase and boring as everyone elses, i.e often the same family demographics, you may feel to have done everything correctly when engaging with potential investors. Logically and based on the advice of many mentors, boot camp lectures and web based resources, requesting cash should eventually work, if you and your team do it long enough.
No, probably not.
Even after the 100th time, learning and modifying your strategy and presentations, this approach may not bring you any further. You will remain you, intelligent, possibly boring and well educated.
May I suggest getting a few domain and industry experts on your 1) board of advisors, 2) documentation and 3) multimedia, to add a VERY visible and differential personalized advantage ?
This approach can also convince those early prospects to make an initial purchase and contribute to your sales growth… provided your operational logic and intelligence are still included.