Reference letter

Hello, I have to write reference letter. Can you check if I did any mistakes?

REFERENCE LETTER Warsaw, 28.02.2017

We hereby confirm that Jan Kowalski was employed in XYZ sp. z. o. o. from 20.08.2012 to 10.02.2017. He worked in the position of Samsung Premium Reseller’s Telephone Customer Service Specialist. During his work in our company Mr. Kowalski was responsible for:

• Samsung.pl online store customer service
• sales of Samsung products and third party accessories for individual and business customers,
• consulting on selection of complex solutions,
• technical support of Samsung customers,
• handling of service requests,
• participating in quality audits (individual average result 100%, while team average result is 82,21%).

Jan Kowalski completed the training programmes listed below:

• Samsung Sales Training and received the Samsung Product Professional Certificate.
• Samsung Customer Experience Management led by Miroslaw Mazur
• Technical support training on Samsung products
• Several product training.

Jan Kowalski was conscientious, dedicated to his work and was very responsible. All these features guaranteed' excellent work. We found also that Mr. Kowalski’s creativity, organizational skills, and ability to work effectively in stressful situations helped to hold successfully his role.