Delsey Combination Lock I Have A DELSEY Suitcase And Need To Know How To Change Combination Lock?

I have a DELSEY suitcase and need to know how to change combination lock? - delsey combination lock

I have a Delsey suitcase, I did in 1994 and I have to change the combination lock. Delsey customer service, you want the serial number, but I can not find him. Who and how one has to change it? I really need help!