Companies have a tendency to close up. Paradoxically the more successful they are, the more closed they tend to be, trying to protect what they have while focusing all the energy on maintaining the pace. This is exactly when companies should make an effort to open up. Here are 3 small suggestions:
Organize open public calls (webinars, Zoom calls, conferences) where anyone can ask you anything, and your experts answer on spot.
Try to partner with a new expert, every month
An expert can be an individual or a company, someone in a new field which is interesting to you. Maybe it works out once a year, but the process itself is inspiring.
Open competitions with rewards
Offer a reward (product, cash, partnership, etc) for a solution to a problem that you have, and promote the competition.
Above suggestion are not only great for innovation and openness, but also for brand positioning and promotion. Your brand will be perceived better and your company will increase interactions and sales, probably at a lower cost than other methods. And if your customers are not reacting to above, then take this as a sign that your brand is loosing its position and you should fix that.