1--- Red Squares: 2 or more Control Points have exactly same X Y Z so overlaped !

Pass in no Unity
2 --- You have 9 curves overlaped! So move one and kill other curves :)

Then clean them : click a red point kill till only one"/>

for the angle's curves clean maybe like this (there are many methods)circles then Blend

Trim by circles then Blend



When all is done join all - rebuild - you wil have a clean curve :)