The reason for your account's inaccessibility determines what happens to your balance.
If you were simply logged out and are unable to log back in, your balance will still be available once you log back in. Similarly, if you were banned, your balance will still be there once you regain access to your account.
If your account is inaccessible because you deleted your account, your remaining balance will be lost. Please be mindful of this when you are deleting your account.