20% Incoming HO Preparation success Rate ?
Ok, so the problem is either:
– congestion in the cell
– hardware problems
Since you say there is no congestion, then you should focues on the hardware (or even the BSC database). I suggest you delete all neighbours and recreate them, even delete the cell and recreate it.
You can ask the local TAC to have a look to your BSC database.
If it’s still not working, try changing the SUM card (perhaps… but i’m not sure)