How do I re-insert the water tube to the ice maker water source?

How do I re-insert the water tube to the ice maker water source? It was clogged so I removed it by pulling it out. There is a rubber hose extending from the back of the freezer which connects to a 3" long metal connecter tube which connects to another rubber section which feeds the ice maker. I am unable to fit the metal tube into the hose in the back of the freezer. Kenmore side by side about 7 years old.