A plumber if you do not want to raise the level of the soil around the clean out.

What is the clean out made of?

Cast iron?
Plastic?

Your applicable code may require the cleanout to be above ground. Making it taller will address the tripping issue. But I imagine that seeing it at all is one of your concerns.

I think it's made of cast iron. It's about 2feet away from the house but in the cement driveway. I don't think making it higher would be a solution because it would prevent 2 cars to park in the driveway.
Weird, isn't it?
Could a plumber cut it down and make sure it's even with the driveway ?
thank you for the responses.
Jeannette