E 320 Bluetec Oil Cooler Problem
 

On March 2022 I found a oil leak on my 2008 Mercedes Benz E 320 Bluetec
and found it was from the oil cooler inside the V of the engine block.
The car was sent to a certified Mercedes Benz mechanic which had the issued resolved using OEM parts. The mechanic gave me a warranty of 12 Months or 18000 Miles. At the time of the repair the car had 144490 K Miles and now, 02/2025 the car has 155290 K Miles totaling 10800 K Miles after repaired.
As I retired, the car is 95 % of the time on my garage, not in use.
The question is: Is it supposed these oil seal to go bad so quickly (10800 Miles) as happened with mine?
I know that the parts used are OEM parts including a new set of all o-rings to re-assemble all parts taken apart to reach the oil cooler.
Are there any suggestion about this issues?
Thanks

From everything I've ever read on this issue (not having an OM642 myself), this is WAY too early to go bad again....especially if the updated o-rings were used.

Whoever did work must have missed something.