Contact Customer Support using this form and say that you need immediate help as you will be travelling in some hours.

https://eurail.zendesk.com/hc/en-001/requests/new

 @Magdalena Immediate help needed.

Thank you, I have sent email using the form above already, waiting for reply.

Still have not received reply.. how should we do as the train will be departing in 2 hours

Have you checked for app updates? Check the version under More and scroll to the bottom. The app version should be 23.2.0. If it's lower, please update and try the activation again.