Ensure you have every numbered part in the same folder (e.g., part1.rar , part2.rar , etc.). If any part is missing, the extraction will fail.
This usually means one of the parts (like your Part 2) was corrupted during download. You will likely need to redownload that specific part. StarlinkBattleForAtlasv0NSP-xcinspdotcom.part2.rar
Use software like 7-Zip or WinRAR.