error: unable to upgrade connection: container not found ("wordpress")
by looking at your output, I think your containers are crashing. first pod crashed 993 times and the second one crashed 87 times. You can check logs of the containers/events of the pods
kubectl logs {{podname}}: for pod logs
kubectl describe pod {{podname}} for detailed description.
As suggested by @mdaniel in comment check for ports also.
Are you able to access application on nodePort?
The problem may be that the container hasn't been started yet. Use
kubectl describe pod <podname>to see if you can view a message such as:
Normal Created 19s kubelet Created container containerNormal Started 17s kubelet Started container containerThe container will have been created and you should no longer see that error message.