There are situations when you need to restart the REXYGEN runtime core (RexCore) on the target device. You can do so by running the following command in Linux terminal:

sudo systemctl restart rexcore

Check if RexCore is running:

systemctl status rexcore

The output should indicate that it is active:

● rexcore.service - REXYGEN Runtime Core (RexCore)
   Loaded: loaded (/lib/systemd/system/rexcore.service; enabled; vendor preset:
   Active: active (running) since Fri 2018-06-01 15:23:07 UTC; 2min 41s ago
 Main PID: 511 (RexCore)
   CGroup: /system.slice/rexcore.service
           └─511 /usr/bin/RexCore -l -c /rex/rexcore/rexcore.cfg

If it's not, your algorithm is probably making it crash and you need to remove all the binary files of your project:

sudo rm /rex/rexcore/*.rex

Afterwards you can restart RexCore again:

sudo systemctl restart rexcore

And check that it is running:

systemctl status rexcore

If it is, you can go back to your original activity.