Trezor issue - "The bitcore server does not reply. Cannot connect to wallet"
Try the other servers.

This means Trezor's blockchain explorers (for example, this one: https://btc-bitcore3.trezor.io) are under maintenance, or restarting, or can't be connected (DNS/ISP problems)...

If your Trezor can't connect to Trezor's servers, then it won't be able to make transaction (as it'll be unable to find older transactions, unspent outputs). Try the other servers. If it still doesn't work, contact Trezor support.