re: section 21

Tax Planning and Financial

when renewing an existing tenants renewal we sent new tenancy agreements out for six months with a section 21 notice enclosed as we have always done to protect the landlord if they require possession when tenancy expires. the tenants in the property assumed since section 21 issued that the landlord would only be renewing contract for six months then would require possession again, they never contacted us to confirm this and no other correspondence was sent to them to advise of this, on the date tenancy expired they called into office and handed in keys when we queried they advised had recived notice of possession and we thought it must of came from the landlord herself. We wrote to the landlord as she lives in Italy queired but she knew nothing about property being empty if was then we realised that tenants had been confused by the section 21 notice. We readvertised the property as requested by the landlord at a higher rent and found tenant within one week and are now busy in the process of doing credit checks. The landlord is now refusing to pay our letting fee and advertising cost as due to our mis management she is two months out of pocket for rent, can the landlord hold us responsible for loss of rent as tenants left when tenancy expired anyway?