You will need to give the systems around 30mins (but in rare events it can take up to 24 hours) to finish things off, then you will able to check your balances and new giffgaff number in the 'my giffgaff' section. Once you can see your credit and new giffgaff number online, only then you will begin to be able to make calls on your phone and begin to use any credit or balances. If your SIM hasn't started working 24 hours after topping up, then it may mean something has gone wrong in the process, see below on how to contact the agents - so they can investigate the matter for you. http://giffgaff.com/support/ask
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