Alright.. So, The thing with the new map is. Not everything works the same, What I'm trying to say is that now that there is people working at multiple stores. You must get in a line (If there is one) and wait to be served. Once it's your turn to be served you must tell the worker what you want.
For example,
Player 1 : "Hey! Can I get the White Phone?"
Player 2 (Worker) : "Sure, That'll be ¥10,000."
Player 1 : Pays the Worker ¥10,000.
Player 2 (Worker) : Passes the phone to the buyer.
Hopefully, You get the essence of what I'm trying to say, If not I'll be more than happy to re-elaborate.