I received my KLM voucher. Now how do I use it? Do I have to call in and make a booking to use it? It seems to imply I can use it online but there are so many numbers on my voucher I wouldn't even know what to input. Is is the same process if I wanted to use it towards a Kenya Airlines flight? Also, voucher says it expires from 1 yr it was issued. Does that mean I have to travel within 1 yr of it being issued? Or that I need to book within 1 yr? Thanks!