If you haven't broken any Star T&Cs, please know that the bond they have held will automatically be released either 7 days after you've picked up or 48 hours after you've dropped off– whichever is the earliest.
You could notice it takes between 7 - 30 business days to show back up, which is all depending on your bank/card provider. Please note that once it's back safely in your bank it won't appear as a refund on your statement because it was only held as an authorisation. They appreciate your patience!