My machine only brews 1/2 cup of coffee. I have

My machine only brews 1/2 cup of coffee. I have de-scaled twice within the last week and I get a full cup of vinegar/water, but as soon as I put in a K-cup I only get 1/2 cup of coffee out. The first cup after decaling may be 2/3 cup, but after that the amount of coffee diminishes. This morning when I put in the K-cup the machine made the noise, but nothing came out. I raised and lowered the area where you put the k=cup again and then it brewed the 1/2 cup. I have had my machine for a year..