In previous business meetings with a customer, I mistakenly allowed the customer to leave to see to some task during our meeting and while waited for him. The customer now considers temporarily leaving our meetings to go do something and then come back an acceptable behaviour.
I need to write an email telling the customer that in the future, interrupting the meeting will not be allowed any more and if it happens again I will have to stop the meeting and reschedule it for another time.
How can I politely write this in an email ?
[Edited to add]
- It's a meeting in person on the customer's premise
- We don't bill for the meeting (by the hour), the only bill is for the product we deliver
- I have to notify them with enough time before the meeting, because the customer has his own customers to serve, so they will have to do enough scheduling themselves beforehand to prevent such interruptions from happening