You need to post the average number of employees through a journal. You need to debit code 9150 and credit code 9999. This will need to be done in both the current and comparative year.

If you have posted the journal but the number of employees either doesn't show, or does appear but is not highlighted in blue (i.e. tagged for iXBRL) it suggests it has been edited in a previous period. Click edit / revert to master format. Click deselect all to untick all items and then tick any row that references frs102.xml, reducedfrs102.xml, micro.xml, microv2.xml or employees.htm. Once done click ok and rerun your accounts. The number of employees should now show and the value will be in blue. You can now file to Companies House.