do you mean the desktop with the road and strange icons? that is the root and I have the same problem.
I tried troubleshooting for a while ended up reformatting the sd card and reinstalling pi-top os its been working perfectly since.
Took me a while to find it but I did find it on their website
Giovanni Fazio
I just got a pi top all working fine until it switched me to the raspbian desktop cant switch back keep getting a error open box failed to execute child process pt dashboard no such file or directory???
I dont know what to do someone help!