Facebook Marketplace scam? Can he get his money back?

My twins brothers bought 2 cell phones on facebooks marketplace (through 2 separate sellers.)

They went to their provider to have them turned on and the 1st iphone came on no problem. Apparently, the other iphone was still under someone elses account and they said it can't be turned on until its removed. (Which means either 1, the phone was stolen 2. Its under a leased contract thats not up yet or 3. They simply forgot to remove the device )

I contacted the Facebook guy that sold it to my brother. He said, he also bought it through facebook marketplace but only decided to sell it because he was told the phone was unlocked and could be used with any carrier and that was false.

He ended up giving me the 'original' sellers name, phone number and facebook. I messaged him earlier but have not received a response yet.

I'm going to wait another day or two but if he doesn't respond, is there anything else I can do?

How to IMessage people out of the country?

My sister lives outside the country and she got a new IPhone with the countries number and area code I put her number in my phone and try to text her and it doesn't turn blue help please.

How do you block unknown phone numbers on iPhone 7?

I've been getting unknown phone calls from marketing people and people from other country's and it's annoying the f***king hell out of me. My dads been getting the same thing. Now I'm not sure weither to believe it or not but one of my dads friend told me that the president legalized phone marketing for making business. Weither that might or might not be true I would still like to know how to block these f**kers from calling me.

Need a reliable phone?

I have an apple iphone 6 right now, and to be frank I strongly dislike how the "updates" slow my phone down… Pretty pathetic. I need a phone thats reliable, has good battery life, and features such as a removable sim card and battery, as well as good build quality (maybe even water resistant I don't know). I don't know why phones are so damn difficult to make well, but I'm tired of my phone being a little *****. Are google phones good? Like the pixel?

I don't want stuff like snapchat and instagram, just spotify and GPS. Thats all I need. Please help me!
Thank you kind people.

Added (1). I forgot to mention I use verizon.