They installed Facebook too.
The sim is with a sub company of vodafone and the sim was in the phone for a few months before it did this.
You should go ahead and ask their customer service representatives why is that they have installed facebook on your phone. That is your concern right and you have to stand for it!
There's a 3 hour hold with Vodafone. I could try calling at 4am tomorrow although there will probably be the same wait regardless.
I suggest to take his advice as well as please reset the sim settings you can find under "Network and internet" this is stop all the sim access apart from calling and messages service.