Saad sh

Hi, I need to know how to fix the rubber seal of the window from outside as shown in the picture. Where to buy a new one ? And what is the formal description and OEM number for it ?

I have the same issue with the Tahoe 2015. Just got it a week ago and since the start I experianced a vibration at 66 mph which let me feel I am inside a plane. I went to the agency and they said send it to the workshop and ask them to check the tires !!!!