Echo Supermarket in Gravesend

Went to return a parcel today and there was two customers in front of me. When it was my turn, the man screamed at me, ushering the customer after me to come forward. The customer advised him I was next in the queue and he said "NO! NO! ". I asked him why he was being rude and he just carried on shouting at me, telling me to look at the queue (only 3 people after me). The customer behind me, again told him I was next and he just didn’t listen and carried on shouting! I left the shop after he continues to shout. As a regular customer I will never shop in the store again!!