I wholeheartedly apologize for the oversight.

Meaning

A sincere apology for a mistake or failure to notice something.

Examples

• John: 'I'm so sorry I missed your call; I was swamped with work.'
• Alice: '<b>I wholeheartedly apologize for the oversight.</b> I should have checked my messages more diligently.'
• John: '<b>I wholeheartedly apologize for the oversight.</b> I'll ensure we have a clearer action plan in the future.'
• Alice: 'The deadline was missed due to unforeseen circumstances.'