First I'd be sure I was signed into my Google account in the Google Play store app. The Play store app might not show apps that are not compatible.
https://www.cnet.com/how-to/find-all-the-apps-youve-ever-downloaded-on-your-phone/ has a very important link. I'll set it on it's on its own line:
https://play.google.com/apps
I upgraded from the samsung s7 edge to the samsung s9 and now some of the themes I purchased didn't show up. Is there any way to get them back? I can't even figure out where they were stored on my s7.

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