Noisy belt Merc GLC

[dba7108]

Hello, looking at a GLC 2.1D for my wife, it's a 2015 with 125k on the clock but full main dealer history. The car did have a receipt from main dealer Merc for work on the "V belt", is this the item in question on the video? It seems to be making a noise. The dealer who I am purchasing it from said they will investigate it before I commit to buy.

Any ideas please what it could be

https://youtube.com/shorts/dc4-EESmS8I?si=LLWQXaOn...