Coffee preparation only trickles down

Coffee only drips into the cup

Hello everyone, I hope to find help here. I have a "Viesta One Touch 500" and only 250 cups of coffee on the speedometer. Unfortunately the coffee only trickles into the cup instead of tiling.
Now I
took
the brewing group
out and cleaned, I had also removed the fine filter and saw that this was completely clogged. So this cleaned and also made the test with back light - completely clean! So after drying again everything assembled and a coffee left out.... The joy was great - everything works - the first 10/15 sec. afterwards it dripped again! Can
I
get
a
tip
here
?

Thank you

very much in advance,
kind regards,
Nico

Your machine's calcified. Please start the decalcification program.

Viesta One Touch 500 with 250 covers is used only at Christmas

Check the grinding degree to see whether the ground material is too fine and whether the sieves in the brewing unit are free! Otherwise, as the previous speaker said, decalcify. When preparing, pay attention to the pump, once one (saeco) had exactly this error picture by a defective pump had.

Mine has 9500 covers and to date need 2 seals on the steam heater, the appliances are really great!

Greeting Holger