Renault Megane 1.9 dci 2002 it make loud noice above 40km/h

So car was on a small service and i pick up the car 2 days later from my sister she say the engine dont make any wierd noice. Then i drive it for about 30min and i realise the right side on the engine is making louder noice from above 40km/h. Noise is like from belt i am not shure because it will make noise below 40km/h can some ome solve this problem?