I've managed to do it now, go to the home screen of the Samsung members app and go to benefits, should have to scroll to the very bottom and you'll see the promotion, click it then follow the instructions. You'll need an invoice as proof of purchase and your imei number etc but its all very straightforward.
A COMPLETE RIP OFF FROM SAMSUNG. Beginning to look an d feel like all of you and myself included, have been 'had over' by Mr Samsung himself??? Looking at all the posts (and there are many on this issue?) It's been difficult or even impossible to claim your 'free buds' when ordering a new S21,S21+ or S21 super bionic mega phones alone with the Samsung Tag. So I got to find my receipt to prove the date that I'd ordered and paid a 'upfront cost?'. Found the said receipt, checked the date of the transaction and to my freak'n surprise the date was 22/10/......wait for it....wait... it was 22/10/2019⁉️⁉️⁉️. What da freak is that about then? Has anyone else been had over by this issue or possibly not even NOTICED. Let me know if you've come across this scam looking freebie from Samsung