Help with Apple Id
So recently I bought some new music and I accidently deleted a song. So naturally I went to redowndload it off of my apple ID where I bought it however, when I tapped to download it it told me "This Device Is Already Associated with an Apple Id. Recently I did sign into a friends Apple ID to download music however I logged back into mine no problem and I bought music back on my apple id no problem. Later that day I somehow got the song back once I had synced my IPhone and my mac book together and I thought that the problem was over. But later that night I bought an album from the ITunes store on my apply Id. It charged me and downloaded to my computer but when I try to down load it to my phone (the device that ii bought it from) It gives me the same error sign as before. I haven’t connected to another Apple id since I went on my friends and I bought music directly after that no problem this problem is new. Please help, thanks in advance! (Sorry if this is in the wrong Community in new to this)
iPhone 6, iOS 9.3.2