Silver Keys

my silver keys are not been added to my account. Can someone Please let me know why or what to do

can you send a picture?

Silver keys are used to unlock departure or arrival slots and cannot be bought.

Is your question about silver planes?

When a plane takes off, You get keys

When some Planes take Off you get Silver/White keys. WHAT are there

they are a way of getting more departure slots for your planes or arrivals without the need for money. you can find them in the derstination menu.