Dynamic QR Codes will be deactivated at the end of the trial period.
If you want to reactivate a specific QR Code, you need to upgrade the account the QR Code was created in.
To upgrade, log in to your account and go to Account -> Features & Pricing.
It’s not possible to reactivate a QR Code by creating and upgrading a new account. It’s also not possible to reactivate another QR Code by creating a new QR Code with the same content.