Only Customer Support can help with this. Use the link to contact them. It is important that you write your pass number and that you are currently travelling so that your request can be correctly prioritised.

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

You can also try to contact Customer Support through social media.

Hello Anna, i just tried and add my pass into my other phone that i have. And it work successfully. Probably the agent have disconnect my pass from my stolen phone. Haven’t receive any email stating that they already disconnect the pass, but it work now on my other device. So i believe it working now.

Submitting a request was indeed what you have to do. Important is that you include the pass number (from the confirmation mail or your Eurail account) and the date when you need it, so that it can be prioritised correctly. A concrete date, not "urgent” or "asap”.

Support also work during weekends (not sure about Christmas though) and they normally reply to such cases within a few hours.

If they haven't replied by noon CET, it may help to contact them on twitter.