Hello @Ly Duong - Thanks for reaching out.
If the subscription has not lapsed then an admin must have disabled it.
If you have an admin account you can re-enable it through the Azure Portal toggling Enabled for users to sign-in? to Yes:
And make sure the subscription is still active and the application is not disabled for that.
If the above response helped, Please feel free to "Accept as Answer" so it can be beneficial to the community.