Avast SecureLine VPN Multi-device shows in one pc but not the other one

i signed up the Avast SecureLine VPN Multi-device free trial. After that, it’s turned on in one of my Windows pc, but on my the other pc, despite showing “Active” under “My Licences”, when I go to Privany / Secure VPN, it’s off and require me to “Buy” or “Free Trial”.

If I tried to enter a licence activation code or insert licence file, it rejects both.

So what can I do to turn it on on this second pc? Thank you.

https://support.avast.com/article/Troubleshoot-activation

Thank you for the link but it did not work.

Contact support: https://support.avast.com/contact