You can only update your Birthday and Gender once in your account settings.
If you're unable to update your Gender or Birthday, it may be due to one of the following reasons:
You’ve already used your one-time update for Gender or Birthday.
You cannot change your Birthday since it was verified through ShopeePay’s KYC process, which confirms your identity and prevents fraud.
To request a change, you may contact Shopee Customer Service. While waiting for a live agent, you can type keywords related to your issue via Chat.