Almost got scammed when cleaning the exhaust fan

Very early on a weekend morning, my mother-in-law said: "Let's clean the range hood today." Then I took out a business card of a cleaning center and called the mobile phone number on it. After contacting the staff, I hung up the phone and looked at the business card in my hand. It was written that this lady is a technician. My mother-in-law said, "The technician should be able to clean it thoroughly."

Half an hour later, the technician arrived. Watching her busy in the kitchen, both my mother-in-law and I began to doubt. She stood on a chair for a long time trying to disassemble the range hood from the wall, but she didn't seem like a real technician.

Even though her skills weren't very competent, the technician was quite particular about cleanliness. She kept asking us to pass her newspapers, almost wrapping the range hood into a big brown package. Ten minutes later, the range hood was finally taken down from the wall. The technician then said, "Before I start working, I have to tell you that there is only one blade left in the exhaust port of the oil fume machine." "But we just replaced it with two new blades last year during the cleaning. If there is only one now, where did the other one go?" "I don't know, but you'd better check it yourself first." Indeed, in her chubby arms, there was only one blade left at the exhaust port of the range hood. The technician said, "Last year, you encountered a scammer, he replaced your product with a fake one."