Where was the ‘network fault’ ?, I doubt the charge was for altering a setting on a phone , much more likely that the fault was on something OR are not responsible for , ( customer equipment , extension wiring , extension sockets etc , or damage not considered fair wear and tear , like spilled liquid into the master socket ) or it’s a mistake and should be challenged.
When someone raises a fault , the line is tested , should the test indicate a fault at or near the customer premises, they should be ‘warned’ of the potential for charges , should the fault be on something OR are not responsible for ( basically anything within the home except the master socket ) the fault is only progressed once the end user accepts the potential for charges , so charges shouldn’t come as a complete surprise, it’s a requirement that the customer is told of this possibility, the engineer doesn’t need to confirm anything , it’s the description of the fault remedy that dictates if a charge is due , and it’s a ‘back office’ function, to raise the charge, not a tick in a box for the engineer
It may seem harsh , but ( for example ) say a customer had a Sky TV box connected to the phone line , and the Sky box developed a fault that interfered with the phone line , the customer doesn’t do the self checks ( like removing all equipment form the line ) assumes the fault must be on the line and simply calls out Openreach, if all OR have to do to restore service , is disconnected the faulty Sky TV box, then the charge for the unnecessary visit is justifiable.
Obviously ,we don’t know what the fault was and what was done to fix it
