Hello Rosnani, tips on how to get a job especially for customer service. First thing first, you need to check the requirement of the job itself. Why they company rejected you? The big reason it must be because the qualification is not suitable the job position. Other than that, I recommend for you to pick up an extra skills, the best would be language skills especially in customer service field. You need to emphasize your communication skills inside your resume in order to ensure that you're suit with the position.

I hope my answer helps you accordingly.