I purchased a new IPhone 7 in January. Before purchasing it we synced my old IPhone 5 to the cloud. At the Apple store they synced my new phone. I did not check right away to see if everything was on my new phone. I mostly listen to one playlist and it seemed like I had all those songs. But, yesterday I tried to play another playlist and it only had 9 songs. I know that previously I had over 300 songs and now my phone only shows about 100 songs. What happened and how can I retrieve the other songs?