I've done exactly what you said before many times. If there's a software decompression error, it won't be able to decompress the first layer, but after the first layer finishes decompressing, it reports an incorrect password for the second layer.
I'm using WinRAR 7.20 and following the instructions, but I keep getting the password wrong for the second layer. I even tried online support for direct extraction, but the password is still incorrect.
Could you please double-check the password at the second layer .