You need to contact Customer Support and ask.

You can use this form:

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

If you are planning on travelling during the next weeks clearly state that when you write to Customer Support.

If the details on your mobile Pass are incorrect our outdated and you can’t change it yourself, please get in touch with Customer Support. If your Pass has not been activated yet, they will be able to change the information for you.

They can help with:

• Adjusting your name (in case of typos, or name changes due to marriage and other legal name changes)
• Adjusting your ID/passport information (in case or typos or ID/passport renewal)
• Adjusting your date of birth

Is your country of residence incorrect?

Unfortunately we can't update your country of residence after you've purchased the Pass. This can only be done by ordering a new Pass with the correct country of residence and requesting a refund for your old Pass (a Pass exchange).