Offering an apology
I’m sorry that this mistake has been made.
Please accept our apologies for the inconvenience that this has caused you.
I can only offer my wholehearted apologies.
I understand your frustration.
I can see how this situation must have caused you stress.
Offering a solution
I’d like to offer you a complimentary…
As a gesture of apology, can we offer you…
We will do everything possible to ensure that this doesn’t happen again.
We appreciate your comments and thank you for your understanding.
Book a Skype lesson to practise these phrases and more in conversation.