Hello Ireland,
Welcome to Microsoft Q&A forum.
Regarding your question about your game license. May I know when and where did you buy the game? I see that you mentioned a migration, which I will assume for now that you bought the game on Mojang site minecraft.net.
Even though every Mojang sites has to migrate to Microsoft account, the store and transaction history of the 2 accounts remains separated. That means if you bought the game earlier at Minecraft.net (java edition), the order won't appear on your Microsoft account, that lead to the Microsoft Store (Bedrock edition) said that you don't own the game.
Have no worries, your license is still there; in order to play the game with your license, you can download the game directly from Minecraft.net, or download the Minecraft Launcher in the Microsoft Store and sign in to it with your Microsoft Account. The java edition should recognize your license.
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