If you get no error message how do you know it has not been saved?
Are you sure it us just the case that you cannot find it again once it has been saved?
In the Libraries (Shift+F) tool, click the Footprints tab and look in Workplace.
Does this help?
[https://easyeda.com/forum/topic/Parts-do-not-appear-listed-in-Personal-Library-after-clicking-Favorite-149f7976db1542918a7425cc9274d8e1](https://easyeda.com/forum/topic/Parts-do-not-appear-listed-in-Personal-Library-after-clicking-Favorite-149f7976db1542918a7425cc9274d8e1)
Our website uses essential cookies to help us ensure that it is working as expected, and uses optional analytics cookies to offer you a better browsing experience. To find out more, read our Cookie Notice
Brand new interactions and interfaces. 
Easy to use and quick to get started. 