If you provide a service and you’re getting paid for it, the buck stops with you.
If there are problems or delays, it is your responsibility to resolve them and to do what’s right with the customer you are charging.
To just say that there has been a problem or delay and it’s outside of your control is not good customer service.
Yes, things happen that can’t be controlled. Problems arise when fixing or doing something. Delays happen with shipping inventory or parts.
But in most cases, there is always something further that can be done to keep the paying customer happy and informed as to what is going on and the details.
Communication is key in these types of scenarios.
When there is a problem or delay, go that extra mile in offering a temporary solution or at least explaining what has happened, why and what is being done about it.