There are warnings tonight that the so-called 'bedroom tax' is causing chaos and confusion, as thousands of people who thought they were liable to pay it are discovering they're not.
Under the rules, anyone who has been in their home since 1996 or before - and has continually claimed housing benefit - does NOT have to pay.
One Cardiff resident told ITV News she was 'outraged' at having to watch people in her community downsize when they didn't have to, as well as the fact that she might now be owed money herself.
The Department for Work and Pensions says it is looking at the issue carefully and will act as necessary.
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Adrian Masters and Andrea Byrne present Monday's special edition from Edinburgh and Cardiff.
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