"Only because I used samples and loops"
Well, it's probably because premade samples and loops aren't allowed in the first place. Even if they are labelled as royalty-free or free to use, using those is against Newgrounds Rules.
List of Audio Guidelines are here:
https://www.newgrounds.com/wiki/help-information/terms-of-use/audio-guidelines
Additional info regarding the usage of loops:
https://www.newgrounds.com/bbs/topic/1451597
If you made something original and still got copyright claimed for it, then you can appeal it. Just follow the instructions you get in a PM and DO NOT close the appeal. A lot of people seem to accidentally close their appeal, which means it gets discarded and is no longer open for review. There is also an audio appeal thread in the forums.
Diamondmanpixel76
You're facing this issue as well?