Redis Crashing after Deleting Vars

Question

What am I missing with my variables? I was deleting un-used ones but some must be required even though I am only doing internal connections.

```
REDIS_URL="${{REDIS_PRIVATE_URL}}"
REDIS_PRIVATE_URL="redis://${{REDISUSER}}:${{REDISPASSWORD}}@${{RAILWAY_PRIVATE_DOMAIN}}:${{REDISPORT}}"
REDISPASSWORD="${{REDIS_PASSWORD}}"
REDISHOST="redis.railway.internal"
REDISPORT="6379"
REDISUSER="default"
```