IT Technician *****ing data using our network password

The technician installing our home network did not set it up properly, even after being called back. I eventually figured out myself why the internet was not working and simply moved the devices around, which should have been done/tested by the technician.

Besides that, the technician took advantage of having our network password by using all of our data in less than an hour. He then pretended not to know why our data is finished (I suspect he thought we had uncapped and then got a surprise when finding out we didn't). We then topped up our data while he was here and within less than 30min used that up as well, while sitting in our drive way, after we actually thought he had left after the job was done. The disrespect and nerve these people have to use our password just disgusts me! We will never use their services or recommend their services again.

I did phone to speak to the manager, after which I found out this person who stole our data WAS the manager. I then asked to speak to another superior and he would have phoned me back, which he didn't. They obviously don't care about this kind of thing happening! I suspect it is a very small company with like three people running it, people who don't care about customer service or customer privacy!