Fixing apps is a process of checking the status of running objects and seeing what's wrong, then fixing up the YAML and redeploying.
If the spec isn't valid you'll get a useful error from Kubectl
Remember the relationship between objects - you'll need to investigate with get and describe for Pods, ReplicaSets and Deployments.
If the spec isn't valid you'll get a useful error from Kubectl
The relationship between Services, Pods and container ports is what you need to investigate.
A port forward is a useful way of checking the application Pod directly.
Need more? Here's the solution.