SIB1 acquisition issue in different Freq/PCI scenarios

Hello Experts,

I have a query:

1st Scenario: Freq are same but PCI is different
As we are testing 4x4 MIMO, we are able to search first cell but sib1 acquisition is getting failed for 2nd cell.

2nd scenario: Freq are different, but PCI’s are same.
This time we are able to see cell search passed for both the cell.

What might be the reason?