Open Level

Hello i am having trouble following a YouTube video on how to make UE4 2d games, this is the video i am following Blueprint Creating a 2D Side-Scroller | 03 | Live Training | Unreal Engine - YouTube .
Some reason i cant get past the time on the video, 46:19, it keeps on messing up, i watch more of the video for the guy show another way to load up level why’ll choosing them.
but it did the same thing here is a picture of what i have dong and the message i get. Let me know if any one can help me.

Thanks for your time to check out my problem.