It says that my game Forza Horizon 4 isn't available to play

I would recommend uninstalling and then reinstalling the game on your PC. I have provided the link below which walks you through doing that. It's possible that some of the game files were corrupted somehow which is why it is behaving as if it is unavailable on your account. I am making the assumption that you are indeed logged into the correct account of course. Before you perform the reinstallation it might be worthwhile checking your order history in your Microsoft account to ensure the order wasn't reversed or refunded for some reason which could also be a reason it is now unavailable. If you continue to have difficulty after you reinstall please let us know so we can continue to troubleshoot the problem for you.

Uninstall and reinstall game on Windows 10.

Hey Luizinho,

Forza Horizon 4 is part of the Xbox Play Anywhere list as referenced in
MajorNelson.com as well as under the capabilities of the game in our
Microsoft Store.

You can play forza horizon 5 if you own it

But if you only downloaded it via gamepass you don't own it

Forza horizon 4 is available though for core

I found that I can't sync, get my old data back. But, I found a way to get the forza horizon 4 in my second account! In Microsoft store it says that I can play forza horizon 4,or buy to my own. Does this mean that I have to buy the game? I think no.

Hello ReginaldoDe Oliveira1,

Thank you for your post. I understand you are experiencing an issue with playing Forza Horizon 3. Forza Horizon 3 has been removed from the Microsoft Store and is no longer available for download from Game Pass. The only way to obtain the game now is if
you have a redeemable code for the game. If you'd like to play a racing game via Game Pass, Forza Horizon 4 is still available for download through the subscription.

I hope this information helps!