>>10510013 (lb)
See the format here.
https://www.youtube.com/watch?v=u7uUQlZrI34
? indicates the start of parameters
v= indicates the video parameter followed by the video ID
You probably are attempting to use a link with extra parameters:
https://www.youtube.com/watch?v=u7uUQlZrI34&t=timestamp&x=something elseasanexample
As another anon said, trim the url where the & begins.