I beg your pardon.

Meaning

A formal apology for something you have done or said.

Examples

• John: '<b>I beg your pardon</b>, I didn't hear you correctly.'<br>
• Alice: 'I said the meeting is at 2pm.'
• John: 'Oh, I'm very sorry.'
• Alice: '<b>I beg your pardon</b>, but I think you've mistaken me for someone else.'<br>