Withdrawals work in a similar way (as seen in the video below). Click on withdraw, enter the amount you'll withdraw from your "Savings account" to your "Available balance".
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Step 1: From the savings tab, select 'Send'.

Step 2: Enter the amount you'd like to withdraw.

And that's it! Your funds will reflect as 'unused funds' under portfolio.

See our guide on how to withdraw it to an external wallet here.