A Frustrating T-Mobile Business Service Experience

I started using T-Mobile's business service, and right from the beginning, I've had issues with the setup. The salesperson who assisted me is now unresponsive, and when I tried to contact customer service, they asked for a PIN code that I was never given. This forced me to visit the T-Mobile store inside Lakeland Square Mall, where the service I received was even worse, particularly from the store manager, Arana.
Upon arriving at the store, we waited about 20 minutes to be helped. I noticed that out of five employees, only two were assisting customers. I approached the counter where Arana was helping another employee who was with a customer. When she looked up and saw me, I asked if someone could help us. She responded in a very loud and aggressive tone, stating she had new hire employees and would get to us when she finished. To spare the lengthy details, after an unpleasant discussion, I had to wait for her to finish before she would assist me. I believe T-Mobile urgently needs to address the lack of professionalism and provide better training on customer service for its employees.