Hi,
What can be reasons for increase of DL BLER on site considering there is no overlapping, no parameter ambiguity?
Any other reasons?
Low RSRP that gets close to noise level could be one reason.
Did aggregation level for PDCCH increased more for aggregation level 8?
Try to compare.
Or if you modified bler target for PDSCH (should be 10%).
Ok, let me check aggregation level, but it’s less traffic site only 3 to 4 users.
New site. I’m suspecting hardware issue.
Or old remedy: reset on site. 
overlapping means a geographical area where two or more PCIs overlap from 2 or more cells. This degrades the SINR and RSRQ. Ambiguity means parameters not audited or out of the golden parameters list.
In our network, usual dl/ul bler is less than 1%, 0if for any site it’s greater than 5% then it’s abnormal and we cleanup or replace SFP ports connected at DU end for cpri towards rrh.