Unknown issue in Stock Balance Report

#Need Expert support

I’m using ERPNext for the Auto Bricks factory since 2016. Now we upgraded the system to v13. For many years of operation, we made few stock reconciliation. Now the problem is I found many mismatch in “Stock Balance” report.
Please check the attach image,

Issue #01. see the black mark box. there has no item qty in “Balance Qty” column but showing value in “Balance Value”. How to make the “Balance Value” Nill.

Issue #02: see the red mark box, I like to manually update the “Valuation Rate”. How is possble.

Thanks in Advance

Noman Haider