Banned for no reason

I got Gameflip in order to sell ALL of my items on rocket league. I had the app for about a week no problem sold ALL of my stuff no problem. Then when I try and transfer the items I got banned for making a new account after “the last one” got banned. I’d also like to say that the person who introduced me to Gameflip was my brother who got banned surprisingly for breaking TOS. He told I could make some good money off this app which I thought I would until I got banned. I was transferring $145 and out of nowhere it got declined and I got banned. I lost ALL of my money and ALL of my stuff in rocket league. My username was RocketShops13 and I’m pretty upset. I got banned for something my brother did basically. Unless if I broke some kind of TOS I’d understand, but this is really hard to take in.

I suggest contacting Support about it.
Just provide all information. They will ask for more information if required.
They will decide what will happen.