We have been recently asked by one of our clients to go out to one of their customers to provide technical support for a touchscreen issue. We're a courier company transporting their equipment from place to place, we're not a tech company, but we nevertheless accepted to send a driver with some IT background to try to fix the issue with the assistance of their technical support help line. Our guy did everything he could and followed the instructions given by their technical support teams, but at the end couldn't fix the problem.
Few hours later, the management of my company receives an email blaming us for not solving the problem by saying the we have been "unsupportive of a touchscreen issue". I am not happy with this comment as we just followed their instructions and that their own technical team didn't know either how to resolve the issue.
I am tempted to reply to them politely to make them understand that their own tech people couldn't find a solution either on their own equipment. But is it a good idea to reply to accusations from a client? Is is better to just ignore and pretend nothing happened?