@Gaurav hey, the problem substor is solving, did you experience it? Have you lost something due to it ie.. time, money? If so, build a story and do a series educating content creators about the problem and potential solutions. explain why you solved it the way you did and get them to agree that your way is the best way to solve it.
Once you do, you have a brand and then, the next effort is outbound. Like Stefan said, ping as many creators as you could across channels. Keep goals like 3 zoom calls per day and speak about the problem. dont even introduce substor to them.
you can try this and lmk how it goes.