Few things I have remarked on your code that might be the issue
Alright so first off I have read a few dev forum posts indicating to not use the parent argument in the Instance.new() parentheses.
More can be found in this post: PSA: Don't use Instance.new() with parent argument
Another thing I have remarked is that when making the attachments you are attaching an item from ServerStorage then cloning it again and attaching it to eachother, which does not make sense to me.
What I would suggest is set the attachment to the character’s HumanoidRootPart rather than the other item. Another thing would be that the attachment is not Cloning on the Character’s HumanoidRootPart, so you might want to set the Attachment’s CFrame to the HumanoidRootPart’s.
Sorry for being too vague, I’m not used to explaining things properly.