On Having A Manual for Workers

I live in a rental apartment and my building is responsible for fixing all maintenance issues.
Ten days ago I had a huge leak and ever since my place has been a construction site with workers of all kinds coming daily and try to fix the problem.
While they are not MY workers, that is, I did not hire them myself and they do not work for me, they do work in order to get my apartment back to living conditions.
I welcome them everyday with snacks and fresh drinks but I do expect them to get the job done and not be on the phone all day with hours of conversations with their spouses and friends.
In my mind I would never do it in my job and I could tell it slows their work as opposed to if they had just been focused on getting the job done.
So I asked the building management if I could say something and he confirmed to me that they are not allowed to talk on the phone during work. I decided not to give him the names so no one get fired but deal with it myself.
And the next day when the first worker came to work and spent the first hour on the phone with his friend, I walked into the room and asked him nicely if he could make his phone calls after work because he gets the job so much quicker when he is not on the phone.
And from that point he changed completely towards me, declined to touch the drinks and snacks (he was eating joyfully before), slammed the door and turned rude towards me.
So it’s true, I had a manual for him: people who come to work should do their work and not be on the phone. And this thought makes me feel upset when it is not met. So am I supposed to change it to: people who come to work should do whatever the heck they want?