what worked for me: 1\. Disable and stop the neo4j service: `sudo systemctl disable neo4j`
`sudo systemctl stop neo4j`
2 remove the contents of `databases, transctions`, and remove `dbms/auth.ini`
`$ ls /var/lib/neo4j/data`
`databases dbms dumps server_id transactions`
`rm -rf databases/*`
`rm -rf transctions/*`
`rm -rf dbms/auth.ini`
3\. Enable and start service
`sudo systemctl enable neo4j`
`sudo systemctl start neo4j`
4.login via cyper-shell
`cypher-shell -u neo4j -p neo4j`
5\. smile:)

In addition to @Michael Halim what worked for me is this: 1\. Disable and stop the service: `sudo systemctl disable neo4j`
`sudo systemctl stop neo4j`
2 Remove the contents of `databases, transctions`, and remove `dbms/auth.ini`
`$ ls /var/lib/neo4j/data`
`databases dbms dumps server_id transactions`
`rm -rf databases/*`
`rm -rf transctions/*`
`rm -rf dbms/auth.ini`
3\. enable and start service
`sudo systemctl enable neo4j`
`sudo systemctl start neo4j`
4.login via cyper-shell
`cypher-shell -u neo4j -p neo4j`
5\. enjoy:)