Almost guarantee that the garage has overfilled your engine with oil.
This is an indication that the garage you are dealing with doesn't know really what they are doing with your pride and joy, the MAX point was revised and now should be 2/3 to 3/4 the way up between MIN and MAX mark.
As your car is telling you then I'm guessing your car got the software update from the 'recall' that was issued and also a sticker telling you that 3/4 is the MAX level for the oil should have been placed near the dipsick?? It is possible the sticker has been taken off though.
D5's suffered from rising oil level due to regen cycles for the DPF and as such the oil MAX level was revised and lowered. It would have been more beneficial if Volvo had issued new dipsticks as opposed to stickers though.
Resolution: remove some oil and ensure max level is set to 2/3 to 3/4 up the dipstick and then the message will disappear within a day or 2.
