First Hour tutorial - Migrating level problem

Had similar issue when watching UnrealSensei’s 5hr tutorial

to be exact in 3:24:27 , I got similar question
2022-05-16_14h17_07

and when I press YES, it will just not responding, goes to ‘unknown unfinished processing’.
After googled and found this topic, and answer no…
finally begin for copying process:

OMG!