Proof of residence with work address.

I was supposed to receive a parcel from Vodacom on Friday. The deliveryman called me around 2PM on Friday, asking if I have knocked off. I told him, yes I have knocked off at 1PM. He then said he will deliver the parcel on Monday, ok I understood. On Monday, he called me around 3:35pm and asked at what time do I knock off, I told him I knock off at 13:00 and he said "Ah". Again I did not get my parcel. On Tuesday morning, he called telling me that he is going to deliver that day and asked for the alternative address if he does not find me at work. I gave him the address, he was surprised to hear that I am staying 10 minutes away from work. He then promised to deliver. Around 12:30 he came to deliver but he said he needs a proof of residence, that confirms the address written on the parcel. I mean how on earth can I have that type of proof. I am not residing at work, I am only working there. He then took the parcel and said there is nothing he can do because he needs that proof of address. That is how my parcel was returned after missing me for several days.