Technician demanded our Wi-Fi router password

We have just had a terrible experience with a technician visit. We were experiencing sporadic disconnections and at one time lost the internet connection for over 12 hours for no apparent reason. The AI bot could also tell that we were having signal issues, so we made an appointment for a technician visit. 

The tech who showed up was a nightmare. Aside from the fact that he did not act and sound very competent or knowledgeable (he had a glazed look when we asked a basic networking question), but here is the ultimate part of this bad tech visit. When it became clear that we were still not getting the internet signal, the tech DEMANDED our Wi-Fi router's password. We responded that the signal not coming into our house had nothing to do with our router, and besides, we would not not share the password of our device with anyone, let alone someone who had just showed up. He then repeated he needed to have our Wi-Fi password, so we pointed to our router's indicator light showing red, which meant that it was not getting the internet signal (and the modem indicator light did not show connection). And as a technician, he had a portable device that would plug into the coax outlet and enable him to determine whether the signal was coming in or not. Besides, we reiterated that we would not share the router password with him or anyone, for an obvious security reason. But the tech guy insisted that he had to have our router password to check the internet signal and finally said: "I gave you my solution, and you do not take it. I can't help you." He then just walked of our house and drove away. Just like that. Unbelievable. The tech just walked out on us, leaving us with no internet connection as before all because we did not give into his unreasonable, illogical and frankly unconscionable DEMAND to provide him with our router password. Some audacity from an amazing loser.