API Error on finish of (otherwise) successful job

[hubodz]

Hello,
I run ArgoWF v3.5.10. When I try to run example from docs it fails with error as below.

Error (exit code 1): an error on the server 
("Internal Server Error: \"/apis/argoproj.io/v1alpha1/namespaces/default/workflowtaskresults\": 
Post \"https://127.0.0.1:8443/webhook?timeout=30s\": dial tcp 127.0.0.1:8443: connect: connection refused") 
has prevented the request from succeeding (post workflowtaskresults.argoproj.io)

I can see it's the wait container that has this issue (the main one finishes with exit code 0). With longer jobs, it generally logs this error all the time, eventually failing the job itself.

Any idea what could fix this issue?

[hubodz]

I found out an issue on my side - I needed to add a serviceAccountName to the workflow template.