parcels haven't been going back and forth

I have been waiting for two parcels for weeks now. The one parcel was meant to be delivered by 5pm where I work and I stayed at work till 5pm but no parcel arrive. now I being told the parcel will be delivered in 2-3 working days again. I do not know how this company operates because I have asked that my parcels are delivered at my workplace between 7an - 4pm. NOTHING IN WEEKS STILL HAS NOT ARRIVED. not happy at all....