Hi there @mariasulayao. Thanks for posting on Yes Crowd.
We currently don't have a feature where you can link your Flybuys to an existing Optus account to earn points.
We do, however, have a Flybuys promotion page where you are prompted to provide your Flybuys details upon signing up and is available to new customers only.
Hope this helps. Let me know if you have any other questions.
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