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This could be impossible to find the root cause from the UI, so better check in the database content of the following tables:
AO_C7F17E_LINGO
AO_9B2E3B_THEN_ACT_CONF_DATA
The second will contain a row with CONFIG_DATA_KEY = "lingoLogicalId" which is not found in the column LOGICAL_ID of AO_C7F17E_LINGO.
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