Shot not pulling [bambino plus]

We have had a bambino plus for 5 years. It really is my wife’s machine as I most drink pour over. I have done the basic servicing as to back flush, cleaning, descaling. Use only RO water. This past week my wife can’t pull a shot. She presses the button and nothing. The puck comes out soaked but nothing is coming out. I did a full cleaning/back flush. When I run the machine with out the portafilter the water drips just fine. I ran a shot with a bit courser ground and it worked but of course wasn’t the same. Beyond getting a new machine, any other fixes?