I'm having trouble connecting three microservices deployed on Railway (whatsapp-service, openai-service, and db-service). The services are deployed and working individually, but the whatsapp-service cannot connect to the other two.

Technical Details:

• All three services are written in FastAPI

• Using httpx for inter-service calls

• Current URL configuration in WhatsApp service:

  DB_SERVICE_DOMAIN=db-service.railway.internal

  OPENAI_SERVICE_DOMAIN=open-ai-service.railway.internal
  
  Error Logs:
  Failed to connect to db service: Cannot connect to host db-service.railway.internal:8000 ssl:default [Connect call failed ('fd12:ed84:1a2b::35:398f:20a9', 8000, 0, 0)]

  Failed to connect to openai service: Cannot connect to host open-ai-service.railway.internal:8502 ssl:default [Connect call failed ('fd12:ed84:1a2b::a3:a03a:6dd5', 8502, 0, 0)]
  
  What I've Tried:

  1. Using public URLs (.up.railway.app) - Resulted in 404 errors

  2. Using internal URLs (.railway.internal) - Results in SSL connection errors

  3. Modifying SSL configuration and ports

  4. Verifying all services are in the same Railway project

  Has anyone encountered similar issues with inter-service communication in Railway? How did you resolve them?

  PS: Everything worked correctly before when the database was Google Sheets, but after migrating to this microservices architecture, connectivity issues began.

  Any help would be greatly appreciated!