Thank you all for looking a the post, got some help from a user and re-wrtten the code.

In case anyone was interested, here is the fixed version

FROM person p

JOIN accessGroup ag ON p.accessGroup = ag.id

JOIN accessGroupProperty agp ON ag.id = agp.accessGroupID

JOIN timePeriod tp ON p.id = tp.personid

JOIN BusIdentity bi ON tp.busIdentityId = bi.Id

JOIN Context ctx ON ctx.currentValue = bi.description2

WHERE

agp.accessPropertyId = 1 -- access property is AccessLevel

AND agp.content = 9 -- AccessLevel is Administrator

AND p.status = 0 -- person is active

AND tp.busIdentityId = @storeId

AND tp.actualEndTime IS NULL

AND ctx.subject = 'HeadOffice'

AND ctx.parameter = 'Store'

AND NOT EXISTS (SELECT 1 FROM #Operator_new opn WHERE p.logon = opn.operatorCode)