I would need more data to help you. You seem to say that the site is fully operational, no alarm, everything is good. Therefore you seem to believe it is a parameter issue ?
Are there call setup in the cell ?
What are the number of
SDCCH requests & success?
TCH requests & success?
incoming HO requests & success?
outoing HO requests & success ?
If all those numbers are zero, then it is probably a hardware problem : are you sure your antennas are connected ? Do some drivetest around the site, check the BCCH coverage.
Lock on the cell, perform some call set ups, then check your statistics again, see if your attempts are displayed or not.