Hi
You might need a brew head cleaning. It can get pluged with coffee residue and oils. But you could also have a bent injector valve or gate valve. But I would try this first.

Remove the brew unit. Holding the handle, the top left side is the brew head. There is an outlet pipe that exits the front side towards the door (looks like a long "L" pipe). 2screws hold it to the top. Remove the 2 screws while holding the manifold ("L" pipe assembly). Once they are removed, lift the l assembly off (be careful, there is an O-ring, spring and at the end a black rubber disk.
Now remove the brew screen, by holding the screen with your finger and twisting the thumbscrew (remember, thumbscrew), DON’T use the key to install the screen, use your fingers.
Once the screen is out look at where the screen was. There are 2 holes. A big one in the center and a small one to the side.
With the brew unit upside down over the towel, insert a paperclip into the small hole and force anything out the other side. I have gotten worms almost a 1" long from this passage. The paper clip has to go from this side to prevent damage to the seat on the other side.
Clean then reassemble. Brew unit on towel right side up. Drop the crystal ball in first. Then the spring small end first on the crystal ball.
Now the O-ring over the spring, then place the manifold on top of that with the pipe towards the machine. Insert your screws (I turn them backwards a little with a little downward pressure until they feel like they drop into the threads. They should turn down easily, if not back them up a little more ( we are trying to find the old threads) and tighten. Install screen, and tighten with your fingers. The screen just needs to be flush with the bottom of the brew head. That should do it.

Good comments by Guru Bansheracer - however
Q1. I know you have water and steam but is any water being dispensed when you try to make a coffee? Depends on your machine you may have twin boilers and twin pumps - one for coffee the other for steam - the coffee pump may have not be pumping/failed and or the coffee boiler could be blocked ( very tiny 'tubing' moulded inside)
Q2. Have you regularly flushed the machine with decalcifying cleaner to remove deposits that build up within the boilers etc ?
Q3. Ok - coffee is being ground and therefore must be dropping into the dregs container. Is it dry gounds or damp cake like as normal?.
Q4. Do you regularly wash the machine? with mine about every 4 days regardless of there being 1 or 20 cups made I always wash the brew unit and all other removable parts in very warm water ( shake brew unit to remove any water inside) and leave to drip dry overnight. As Guru Bansheracer correctly mentioned, a lot of stuff can build up in the brewhead and with oily beans it doesn't take long either.