The error in your logs is: Problem: channels.notion: unknown channel id: notion . This is what's causing The "Gateway not ready" error.
You need to setup notion correctly to get this issue resolved.

Yeah, there is bit of learning curve using this, Railway has clarified here - https://x.com/Railway/status/2017349208114688377, someone figured it out as well here - https://x.com/dzhohola/status/2017692484810256510

But if you want to skip all that, you can deploy this - https://railway.com/deploy/openclaw-prev-clawdbot-moltbot-self-host (bit of self promo huh :)) It has step by step guide in overview section