The dipstick was missing!
What dipstick forgot to put it back on the previous service!
One of the reasons why I would never purchase a Mb vehicle is down to them wanting the dealer to wrong service interval-most scheme car’s do frequent short journey’s in stop start traffic and cold starts. The oil quality degrades much quicker, requiring the vehicle to need more oil services. Hence why manufacturers often state in the owners manual the correct service schedule to choose based on how the vehicle is used.