First step is to talk to the employee. Ask the employee what he/she did. Everybody deserves a chance to explain themselves.
Don't send the same employee back. The customer has lost faith and confidence in them.
Sometimes customers lie. Some people don't like to pay regardless of the time spent or the work done. Their relucatnce to pay has nothing to do with ability to pay either.
Regardless of who is lying, the plug needs to be replaced/inspected. A short call is a short call. Always spend a couple of minutes - no more than 5 - with the customer reviewing the work done, comment on how nice her home is, ask if there's anything else she needs done (could even work in a freebie), and leave a business card. A cheated customer tells 20 others.
