Forza Horzion 4 take to long to start (0x8027025a)

The game is fully downloaded, It's not still in the queue downloading ?

It looks like you've pretty much covered all there is to try really, maybe try removing and adding your account back to the Xbox, if you have any other accounts on the Xbox will the game launch at all using another account ?

If you could also try this although you may have already. With the Xbox powered on press and hold the power button on the Xbox for 10 seconds, when the Xbox powers off pull the power cord out of the back of the Xbox and let it sit for at least 1 minute with
no power cord. Then reconnect the power cord and power the Xbox on using the power button on the Xbox and try the game again.

Its on the internal Hard Drive

Have you got the demo installed? If so, uninstall it and then try starting the full game.

Yeah i tried everything.

And i was often in the xbox support

Also worth noting is that if you have anything downloading when you try to launch a game that can give this same error code, so if you do have anything downloading pause the download and try Forza.