You should never activate a travel day until just before boarding the train, otherwise you might, as you did, loose a travel day. You can't delete a travel day in the past. A travel day can only be deleted until 23.59 CET the day before the travel day.

You can try to get help from Customer Support but I am far from sure that they will fix it. It is your responsibility to not activate a travel day until you know that you will use it.

Contact Customer Support through this form.

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

Customer Support is overloaded with requests so you need to clearly write what date you will start travelling so that Customer Support can prioritise your request correctly.

Thanks Anna. I have raised a request with the Eurail team. I am travelling from 14th June. And I need to make some reservations also. I am confused if I should go ahead and do it using other travel days it wait for customer service to get back?

Go ahead I would say, don't wait for Customer Support. 

There was a response from customer support team asking for a screenshot but no reply post that. Is there a way someone from this forum can help with this issue? I also contacted Eurail aid office in Switzerland but they were not able to help as well.

Only Customer Support can, if it is possible, fix this. There are some Eurail staff that are members of the community and occasionally they can raise an issue with Customer Support. 

You can check the status of your request in the request database if you follow these steps. 

Use this link to come to the request database.

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

Click "Sign in" in the upper right corner.

 

Enter your email address and Click " Get a password".

If the system doesn't recognise your email address, then there is no request registered and you need to go back to the start screen and enter a request.

If you get a password, you can then log in and look at the status of your request.

Thanks Anna. I have been following up with customer service multiple times but it's not solved yet. The ticket is still in open status.

@Marion @Nanja Can you please help on this? My request number is #195583. I am travelling currently and if I don't get a solution by tomorrow, I will not be able to use a travel day. I understand it's my mistake, but it was because of lack of awareness on how to use the mobile pass.

@Marion @Nanja @Leo @Felipe.iturrieta. Requesting support on this.

Haven't got any update on this so far. I have been following up through email, request in the website, Twitter etc. But looks like nobody responds from Eurail. I have been using Eurail pass for many years but I doubt whether I will buy it again given this experience with customer service. Now I need to buy regular train tickets for a day despite owning the pass. Although I have mentioned the urgency multiple times, nobody seems to prioritize this.