Manx Care's become the third government organisation in a week to face criticism over its handling of a Freedom of Information request.
Information commissioner Dr Alexandra Delaney-Bhattacharya says it took four months to respond to an FOI about the Braddan Roundhouse in 2024.
The response also contained a number of errors.
Manx Care will now have to reconsider the redactions it made in its response and provide a new answer.
The Department of Environment, Food and Agriculture and the Cabinet Office have also faced criticism over FOI responses from the ICO this week.
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