Camunda upgrade from 8.0.5 to 8.1.6

Camunda 8 Topics
1

after upgrading from camunda v8.0.5 to camunda v8.1.6 we are not able to complete any user task that was created before the upgrade. task retrieval, claim/unclaim requests are working just fine but when it comes to completing tasks we see

{
    "errors": [
        {
            "message": "Command 'COMPLETE' rejected with code 'NOT_FOUND': Expected to complete job with key '2251799817760698', but no such job was found",
            "locations": [
                {
                    "line": 2,
                    "column": 4
                }
            ],
            "path": [
                "completeTask"
            ],
            "extensions": {
                "type": "ClientStatusException",
                "classification": "DataFetchingException"
            }
        }
    ],
    "data": null
}

However the process is showing as running in the operate ui, also the task I’m trying to claim has status CREATED in Elasticsearch.

Another issue is that the processes started after the update are not showing in Operate UI, as well as tasks created after the upgrade are not showing in Tasklist UI.

i tried to look into the elasticsearch indices and i can only find 8.0.5 related indices. should the new 8.1.6 indices get created after the upgrade?
looking at the documentation here Update 8.0 to 8.1 | Camunda Platform 8 Docs the upgrade should be straight forward.

is there anything else to be done?

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