communication skills

As a telemarketer I had the opportunity to improve my communication skills. By careful listening, perseverance, resourcefulness and language creativity I was successful in attracting (say something here about how many if possible) new customers. Through my experiences in customer service I have learned how to deal with challenging situations, as well as how to adjust my approach to suit every type of a customer. 

(I would change it a little to stress your success in the previous role. Not 'gaining upon'... 'gaining', 'attracting', 'acquiring' is ok in this context. The order of the second sentence sounds ok. I took out 'patience and kindness' and 'different conflicting' but if prospective employers are particularly looking for these skills and mentioing them in their job descriptions then put them back in. Good luck with the job hunting!)