somehow I have two apple ids. how do i cancel an apple music subscription on the one that I am not able to access on my device?

Some how over the years I have two apple ids and one has been used for my apple id on my latest phone, but the other one was used for media and purchases. This has been the case as long as I know of, but yesterday all of my music and apple music subscription disappeared. In the process of trying to figure out what happened, I entered the same apple id for both and now it wont allow me to change it back. How can I cancel the subscription on the one I am not able to access?

Is there an option to merge two accounts so that I don't lose anything?