HTB Academy Windows Privilege Escalation Skills Assessment

Hello everybody,

i am stuck on the skills assessment part I of the Windows Privilege Escalation module. I have got a foothold on the target, yet can not escalate the privileges. I invested A LOT of time in this machine, tried all vectors presented in the module, with no success. Used different enumeration scripts, tried found vulns (again no success). I asked for help on Discord, but nobody was willing to help/explain. I know that there is some tiny detail I am missing but have no idea what it is. Please help.