What do you define as a 'wallet' ?
If you can access your trezor and view your transaction history inside your trezor, you are accessing your (old) wallet.

If your funds should be on the same account as your old transactions are, it doesn't make sense. It may be a network/sync issue.
Did you check your addresses (those which should have a balance; inside your trezor) on a blockexplorer ? If they have a balance AND are seed as your addresses inside your trezor, it definitely is a network/sync/display issue. 

Since you can access a part of your transaction history your seed most probably is correct (except for the case where you have changed it; do you only see old transactions inside your wallet (without a current balance) or is there actually a balance ?)
Do you remember creating a new seed ?