Battlefield 4 battlelog platoons

I found some players that we work well together. I was already in a platoon. I was attempting to add the new guy's platoon. But there isn't an add feature anywhere. I even left the platoon that I was in, thinking that it would help. Nope. And now that I don't belong to a platoon, I still have my old tag when I play online. The platoon that I am trying to get with is aware that I want to join and was trying to help. Now checking with yall.