The loss of the device that is connected to imKey will not affect your assets, because the private key for your wallet is stored in the secure chip of imKey. Therefore, the loss of the connected device will not have any influence on the assets. Once the connected device is lost, please get a new device and download imToken.
If you have saved the connection code of your imKey, you can simply resume using imKey after connecting the new device to it. If you haven’t saved the connection code of your imKey, you will have to reset imKey and match with and connect to the device. Finally, you can resume the use after importing the wallet and backup it.