Database systems -- small ones, anyway -- can often run in either of two modes: embedded or server. In embedded mode, the idea is that one program and only one program can read and write to the database at a time. This is quite useful for many applications, and allows the database to dispense with the code necessary to allow access among multiple programs, which eats up time, code, and processing power.
In server mode, the database management system itself runs as a separate program, and it is built to have multiple programs access it.
Based on the class in the error message above, you have an embedded database, so the answer to your question is "no, you can't do that in this mode". You can switch to using a server mode of neo4j, I expect, but connecting to it will involve some code changes, and you then have the minor problems of making sure your database system is running when your program runs, etc.
So you can do it with this database data, but you have to change the mode in which you are running the database management system.