Linking Your Wallet
Firstly, if you are planning on transferring outwards, then you will need to link a personal wallet address. [DO NOT link an exchange wallet address]
In order to link an external wallet address, you will need to follow the steps below:
Step 1: Click Your username, or the shield icon in-game, and select the option Link External Wallet:
Step 2: Insert your personal wallet address within the address field under the appropriate wallet type, tick the checkbox to acknowledge that you are not using an exchange address, and then click the save button. (You may see a prompt to sign with the appropriate Hive key to confirm this change. If so, you may sign for the transaction to confirm the changes.)
And now you should be able to successfully transfer assets out towards the newly assigned destination address that you have just added to your Splinterlands account.