HO_out _msc preparation failure

Hi,

I have a problem high HO_out _msc preparation failure in my network for only 1 site.Action done to solve this but the problem still persist.
Action:
1. consistency check on mismatch data- all data seems ok.
2. check adjacency at target cells
3. delete adjacencies at bsc and add back
4. delete/recreate cells

Then the problem gone after rehoming bsc but again appear after a few hours.
Hopefully all telecommunication expert here can help me on this.
Many thank in advance.