This large corporation located in the City Centre of Berlin has the absolute worst customer service…read morein any country we ever visited. We asked one of the cell phone representatives to assist with picking out a SIM card so we could text to USA. One man recommended one brand while another man said the first brand would not work and suggested we purchase the more expensive plan. The first two men spoke some English. After providing our passport, the customer service went from 7/10 to 1/10. Our passport showed USA citizenship: so we are suspicious that this store harbors resentment of Americans. All of sudden, none of the sales reps could understand English. After purchasing the SIM Card and inserting it into the cell phone, it did not work even after about 45 minutes. When we tried to seek assistance from any of the store clerks, none of them would speak English and said they couldn't help us. They motioned us to go up to the 5th floor to find a manager. There was no manager on the 5th Floor so they directed us back to the ground floor. The man who took our passport and entered into the system was no where to be found: he went on a coffee break and never returned. We then attempted to seek help from 2 other sales reps: one was an Asian man who spoke some English: the other was a nasty and rude young woman who rolled her eyes. She was dressed in street clothes and was purely unprofessional. She started cursing in German and ignored us and walked away. The experience was so bad, we will never chose Berlin as a vacation destination ever again. Shameful.