from the MT wiki, that is the process that you need to go through:
Please follow these steps before contacting support:
Upgrade the RouterOS software to the latest version
https://mt.lv/upgrade;
Upgrade the firmware by running /system routerboard upgrade, in the CLI;
Reboot the device and ensure that the unclassified process is persistent;
Create supout.rif file and contact support, describing situation - when exactly the unclassified process shows, how long it takes after the reboot to show, etc.
if you what to know what unclassified means , also from MT wiki:
unclassified - any other processes that were not classified. (does not explain enough)