Since the Minecraft website shows Standard Edition as owned, the license is attached to a Microsoft account, and the launcher is most likely not detecting that license correctly.
Try this in order:
- Verify the same account is signed in everywhere
- In Minecraft Launcher, confirm the signed-in Microsoft account is the one that shows ownership on the Minecraft website.
- Open Microsoft Store and check the profile icon in the top-right corner to confirm it is signed in with that exact same Microsoft account.
- If the Xbox app is installed, check that it is also using the same account.
- Refresh the license sign-in state
- Sign out of Minecraft Launcher.
- Sign out of Microsoft Store.
- If installed, sign out of the Xbox app.
- Restart the PC.
- Sign back in again, starting with Microsoft Store first, then Minecraft Launcher.
- Confirm Store ownership
- Search for Minecraft in Microsoft Store.
- Check whether it shows Owned or Install instead of a purchase prompt.
- Check edition detection
- Make sure the launcher is opening the edition included with the entitlement shown on the website. Context indicates edition mismatches can cause confusion, especially between Java and Bedrock.
If it still shows Buy after those steps, this is likely a license sync / entitlement issue rather than a local launcher problem. In that case, the next step is to contact Minecraft Support so the entitlement can be verified and corrected.