I am using the placement targeting by adding the name of the Youtube channel, however, i keep getting undefined plus this message :
There was an error with your operation. If you were trying to make a change, it may not have saved.
If the error continues, log out of your AdWords account, then log in again and return to this page.
Can you check it by clearing cache and cookies of your browser. Also, you can log in AdWords account in different browsers.
It also generally happens due to low Internet connection.
Did you find any helpful responses or answers to your query ? If yes, please mark it as the ‘Best Answer’