Where you have posted a figure for stock in the balance sheet then there must be corresponding entries in the P&L.  This applies equally for Work in Progress (which has 1050 as the balance sheet code and 5007 & 5207 as the P&L codes).

E.g. A posting of £5,000 in to code 1000 Stock must have a corresponding credit entry of £5,000 in code 5200 Closing Stock (in the P&L).

Also, if there was a posting in to 1000 for the comparative period then there must be a posting to 5100 Opening Stock (P&L) for the current year.

It is also important that the postings are aligned e.g. 1000 = 5200 and 1001 = 5201 etc.  This is required for current year and comparatives