My Platform Needs a Critical Mass to Function – How Do I Get There?

I’ve been building Aytji.com, a skill-based money-wagering platform for gamers. The platform is live, and we have a small user base, but we’ve hit a major issue—our model requires multiple users to be online at the same time for it to work.

I’ve tried different growth strategies:

• Facebook ads ($500 spent, some signups, but no consistent activity).
• Email marketing (low engagement).
• Content Creator Program (incentivized creators to bring in users, but no traction).

The issue is that even though we have users, they’re not online at the same time, so the platform feels "empty." How do I grow my user base in a way that ensures active participation rather than just signups?

Would love to hear any ideas on how to break through this challenge!