PISA email alias forwarding to Gmail issue

Recently, we found that GMAIL no longer accepts SMTP forwarding feature.
i.e. <alias>@pisa.org.hk forwarding to <user>@gmail.com does NOT work anymore.

We have sent an email notification to corresponding PISA members, and seek for an update. Please feel free to reach us if you want to update the email forwarding setup. Please send us an email to membership[at]pisa.org.hk

<alias>@pisa.org.hk and <non-gmail email address>
OR
Your membership no. and <non-gmail email address>

For your reference, we tested Yahoo and Outlook, and they are working well.

Thank you for your attention, and sorry for any inconvenience caused.

Kind regards,