Code Rights
In the section "Code rights" within the User Configuration, assignments and projects can be locked for editing for one or all users depending on the code. This overrides the permissions assigned via Basic Rights and Group Rights.
To restrict an identifier for individual users, first select the desired user . Now go to the relevant line and tick the checkbox in the "Lock" column.
The "LockAll" column, on the other hand, affects all users in the system.
To activate the editing locks, save them using the 
button.
Tips on filtering the table can be found in the article Working with tables.