For example both Cardiff and Vale and Hywel Dda health boards advised that they were unable to record telephone contacts at the height of the pandemic, but other health boards were able to.
Er enghraifft, dywedodd byrddau iechyd Caerdydd a'r Fro a Hywel Dda nad oeddent yn gallu cofnodi cysylltiadau ffôn ar anterth y pandemig, ond roedd byrddau iechyd eraill wedi gallu gwneud hynny.