Formal business letter

She provided me with crucial information that assisted in making a responsible decision. As such, I am hereby commending her for a job well done.
Actually, I had patronized several of your smartphones for the last couple of years. I was looking for a smartphone that would serve my personal and professional needs. It is through the exemplary assistance of your highly-trained customer service representatives, like Ms. Brown, that customers like me keep coming back. I strongly believe that Ms. Brown should be eligible for promotion to a higher position in your prestigious organization.
Congratulations on providing exemplary training to your customer service representatives. I would surely recommend her and your retail store to my other colleagues. Thank you.
Sincerely yours,