Usertask assignee empty string

If I assign the username “” (empty String) via API call, the usertask shows up as “not assigned” in camunda tasklist but cannot be assigned because it is already assigned. This is confusing.

This is how it shows up:
image

This is the error message:
Task ‘68d43e94-187a-11ed-bfb3-f40270f6362c’ is already claimed by someone else.

This is the task data:
{
“id”: “68d43e94-187a-11ed-bfb3-f40270f6362c”,
“name”: “Prüfe XYZ”,
“assignee”: “”,
“created”: “2022-08-10T09:02:34.217+0200”,
“due”: null,
“followUp”: null,
“delegationState”: null,
“description”: null,
“executionId”: “68d43e90-187a-11ed-bfb3-f40270f6362c”,
“owner”: null,
“parentTaskId”: null,
“priority”: 50,
“processDefinitionId”: “digitalization:8:4003c1a6-c9ee-11ec-a6ad-f40270f6362c”,
“processInstanceId”: “8615228a-14a3-11ed-bfb3-f40270f6362c”,
“taskDefinitionKey”: “CheckResultManually”,
“caseExecutionId”: null,
“caseInstanceId”: null,
“caseDefinitionId”: null,
“suspended”: false,
“formKey”: “embedded:app:forms/check-result.html”,
“camundaFormRef”: null,
“tenantId”: null
}

Hello @LukeSWK ,

this looks like a bug. Please file a bug report here.
There will be some more information required, please provide them in the ticket.

Thank you for contributing to Camunda Platform 7!

Jonathan