Fixed it
It appears than when using a app specific pasteboard you need to add if your creating a pasteboard or receiving from it using create YES or No
Copy to Pasteboard
UIPasteboard *pasteboard = [UIPasteboard pasteboardWithName:@"myPasteboard" create:YES];
[pasteboard setPersistent:YES];
//save to unique pasteboard
[pasteboard setString: [NSString stringWithFormat:@"%@",self.myTextFieldHere]];
Paste from Pasteboard
UIPasteboard *pasteboard = [UIPasteboard pasteboardWithName:@"ICPatEditionPasteboard" create:NO];
self.myTextFieldHere.text = [pasteboard string];