Normally instructions would be included in the emails you receive when you've ordered your handset. Have you checked them?
Otherwise, try asking the live chat reps - http://yesopt.us/chat2us
Hi @Babs2112, when did you receive the handset? Samsung advised that customers would have until the 30/11/19 to redeem their gift.
As per the below:
Samsung Galaxy Buds Redemption
1) Once you have your handset, complete the redemption process online @ samsung.com/au/galaxy-offer/
2) You'll need the following details"
3) Within 14 days an email confirmation will be sent from Samsung validating the redemption
Keep in mind: The Galaxy buds will be delivered within 30 days of the email confirmation being sent.The tracking details will be sent in a separate email after the claim confirmation email.