This is why I don't really trust devices like these to store my bitcoins. I can do just fine with cold storage, but have you contacted Trezor's suport?
The problem described in this post has nothing to do with the Trezor device. All it does is sign transactions; it's up to the PC to create a valid transaction in the first place. The Trezor device has no idea how many bitcoins the user has.
OP can very likely just 'forget' the device on the website, then reconnect.