CLK320xxx

I changed my oil & filter 2000 kilometers ago and as I was speeding one day I received this message on the dashboard: "Add 1.5L of oil to reach max level" It didn't leak any, no drops of oil on the floor. So I thought it was burning all that oil and told my mechanic to top it up. Although that we added 2L of oil, I still receive the same message on the dashboard whenever I measure the oil. Sometimes it says add 1.5 and sometimes 2L. So I guess the sensor that measures the oil is broke and I overfilled my car. Now I have to drain all the oil to actually see how much is there. Has anyone experienced something like this? How can I get the oil measurements correct? Thank you.

CLK320xxx

Went to my mechanic, had to drain all the oil out. We put oil again and it read correctly this time.