I downloaded all of my amazon music to my SD card to switch to a new device. So I take the SD card with all of the downloaded music put it in my new phone then sign into my Amazon music account and it says I have no fricken music downloaded. I seriously need a solution to this problem before I go ballistic because after waiting for all my stupid music to download just for it to not show up on the new phone I am frickin livid. Keep in mind it shows up in offline music on my sd card on the old device. I NEED TO KNOW
I'm not very experienced with Amazon Music, but on other sources, when you download music to an SD card, it stays on the SD card. So most likely, your music will not appear in Amazon Music because Amazon Music doesn't know to look in your SD card for the music. If you use a file explorer, you should be able to find your music on the SD card.
If your phone doesn't come preinstalled with a file browser, ASTRO File Browser works pretty well for me. There are a lot of file browser apps out there.
There might also be an option on Amazon Music to import or show music on the device/SD card.