The developer of ECitizen is Jasna Pleho and all inquiries must go to them.
The GDPR gives EU and UK residents a "right to erasure" meaning that you can request app developers like Jasna Pleho to delete all your data it holds. Jasna Pleho must comply within 1 month.
The CCPA lets American residents request that Jasna Pleho deletes your data or risk incurring a fine (upto $7,500 dollars).