Saeco incanto deluxe problem

Good morning.

>Following problem:

My machine indicated to me "decalcify". But I let it sling for 2-3 days, because I didn't have a descaler at hand. As usual, I then added liquid descaler and wanted to start the descaling process. Then she made strange noises, flushed briefly and said only "decalcification completed". I went to the menu and started the descaling process manually. Since then it makes strange noises and I have the feeling that the machine has pressure fluctuations after the warm-up phase during rinsing and also during coffee.

For cleaning:
I clean the brewing group every 3-4 weeks (under running water). The machine can only be descaled on request.

I couldn't find a solution on the internet yet and now hope that you could! Thank you in advance!