@bifelix89
Please do not post a support request without first reading and following the advice in https://retropie.org.uk/forum/topic/3/read-this-first

Asking for help without even trying to look this up or understanding what this means, results in more work for others, even if some awesome members already put work into a clear explanation, is bad (I guess)... Looking your "problem" up in the docuentations/wikis/github pages (or even on google) would have given you the right answer...

However:
This isn't an error... It just means that the scraper could not found the name of the rom (or in this case the hash of it) in the metadata/image database! This basicly means that there is no metadata/image for this game.
You might be able to "solve" this by using another database

Retropie Metadata Editor