Xero Expert needed to assists with COGS and Stock Tracking

I have an issue with Xero which I use for my Netherlands company (I also use Xero for my UK company which is separate). I need someone who is familiar to Xero, COGS and stock tracking to help.

When I started using Xero back in 2021 when the Netherlands company was formed my bookkeeper didn't use Tracked Inventory, over time as PO's and SO's were created stock and COGS was not recorded correclty. 2021/2022 end of year accounts have been filed and the 2023 accounts are due shortly. At the begining of 2023 Tracked Inventory was turned on in Xero. The problem is that the stock level is quite high in Xero when it should be much lower to reflect was stock has been sold.

I have all the PO's since the companys formated, all the SO's (there are not a huge number as my UK company is the only customer for the NL company). I need someone to fix the issue so that the 2023 COGS onwards are correct.

My bookkeeper can assist with any questions regarding this as well,