Previewing songs in iTunes Store

I have been buying songs from iTunes for years. Recently upgraded to Catalina and don't understand why this is happening.

I go to music . I do a search. I find the song . I click on the song for a preview and get a window ad for "1month free music from apple" I click "not now" . The window disappears and I'm back at the beginning. Tried different songs etc. Never able to get a preview. What am I missing here?

Thanks for your reply

Hans

I was able to get to the preview. I guess it involved another step. I needed to go to the Apple Music store. My search didn't originally take me there. I had the full screen with the album and the play arrows and the cost. Not sure where I was there., but clicking on apple music changed the screen slightly and was able to play previews and purchase. So I'm guessing that iTunes is separate from the apple music store, if I understand that correctly. I'm allowed to search from without the store but need to go to the store to preview and buy-right?

Thanks for your help

Hans